An official website of the United States government
The .gov means it’s official. Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.
The site is secure. The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.
- Publications
- Account settings
- Advanced Search
- Journal List
- BMC Med Res Methodol
The case study approach
Sarah crowe.
1 Division of Primary Care, The University of Nottingham, Nottingham, UK
Kathrin Cresswell
2 Centre for Population Health Sciences, The University of Edinburgh, Edinburgh, UK
Ann Robertson
3 School of Health in Social Science, The University of Edinburgh, Edinburgh, UK
Anthony Avery
Aziz sheikh.
The case study approach allows in-depth, multi-faceted explorations of complex issues in their real-life settings. The value of the case study approach is well recognised in the fields of business, law and policy, but somewhat less so in health services research. Based on our experiences of conducting several health-related case studies, we reflect on the different types of case study design, the specific research questions this approach can help answer, the data sources that tend to be used, and the particular advantages and disadvantages of employing this methodological approach. The paper concludes with key pointers to aid those designing and appraising proposals for conducting case study research, and a checklist to help readers assess the quality of case study reports.
Introduction
The case study approach is particularly useful to employ when there is a need to obtain an in-depth appreciation of an issue, event or phenomenon of interest, in its natural real-life context. Our aim in writing this piece is to provide insights into when to consider employing this approach and an overview of key methodological considerations in relation to the design, planning, analysis, interpretation and reporting of case studies.
The illustrative 'grand round', 'case report' and 'case series' have a long tradition in clinical practice and research. Presenting detailed critiques, typically of one or more patients, aims to provide insights into aspects of the clinical case and, in doing so, illustrate broader lessons that may be learnt. In research, the conceptually-related case study approach can be used, for example, to describe in detail a patient's episode of care, explore professional attitudes to and experiences of a new policy initiative or service development or more generally to 'investigate contemporary phenomena within its real-life context' [ 1 ]. Based on our experiences of conducting a range of case studies, we reflect on when to consider using this approach, discuss the key steps involved and illustrate, with examples, some of the practical challenges of attaining an in-depth understanding of a 'case' as an integrated whole. In keeping with previously published work, we acknowledge the importance of theory to underpin the design, selection, conduct and interpretation of case studies[ 2 ]. In so doing, we make passing reference to the different epistemological approaches used in case study research by key theoreticians and methodologists in this field of enquiry.
This paper is structured around the following main questions: What is a case study? What are case studies used for? How are case studies conducted? What are the potential pitfalls and how can these be avoided? We draw in particular on four of our own recently published examples of case studies (see Tables Tables1, 1 , ,2, 2 , ,3 3 and and4) 4 ) and those of others to illustrate our discussion[ 3 - 7 ].
Example of a case study investigating the reasons for differences in recruitment rates of minority ethnic people in asthma research[ 3 ]
Example of a case study investigating the process of planning and implementing a service in Primary Care Organisations[ 4 ]
Example of a case study investigating the introduction of the electronic health records[ 5 ]
Example of a case study investigating the formal and informal ways students learn about patient safety[ 6 ]
What is a case study?
A case study is a research approach that is used to generate an in-depth, multi-faceted understanding of a complex issue in its real-life context. It is an established research design that is used extensively in a wide variety of disciplines, particularly in the social sciences. A case study can be defined in a variety of ways (Table (Table5), 5 ), the central tenet being the need to explore an event or phenomenon in depth and in its natural context. It is for this reason sometimes referred to as a "naturalistic" design; this is in contrast to an "experimental" design (such as a randomised controlled trial) in which the investigator seeks to exert control over and manipulate the variable(s) of interest.
Definitions of a case study
Stake's work has been particularly influential in defining the case study approach to scientific enquiry. He has helpfully characterised three main types of case study: intrinsic , instrumental and collective [ 8 ]. An intrinsic case study is typically undertaken to learn about a unique phenomenon. The researcher should define the uniqueness of the phenomenon, which distinguishes it from all others. In contrast, the instrumental case study uses a particular case (some of which may be better than others) to gain a broader appreciation of an issue or phenomenon. The collective case study involves studying multiple cases simultaneously or sequentially in an attempt to generate a still broader appreciation of a particular issue.
These are however not necessarily mutually exclusive categories. In the first of our examples (Table (Table1), 1 ), we undertook an intrinsic case study to investigate the issue of recruitment of minority ethnic people into the specific context of asthma research studies, but it developed into a instrumental case study through seeking to understand the issue of recruitment of these marginalised populations more generally, generating a number of the findings that are potentially transferable to other disease contexts[ 3 ]. In contrast, the other three examples (see Tables Tables2, 2 , ,3 3 and and4) 4 ) employed collective case study designs to study the introduction of workforce reconfiguration in primary care, the implementation of electronic health records into hospitals, and to understand the ways in which healthcare students learn about patient safety considerations[ 4 - 6 ]. Although our study focusing on the introduction of General Practitioners with Specialist Interests (Table (Table2) 2 ) was explicitly collective in design (four contrasting primary care organisations were studied), is was also instrumental in that this particular professional group was studied as an exemplar of the more general phenomenon of workforce redesign[ 4 ].
What are case studies used for?
According to Yin, case studies can be used to explain, describe or explore events or phenomena in the everyday contexts in which they occur[ 1 ]. These can, for example, help to understand and explain causal links and pathways resulting from a new policy initiative or service development (see Tables Tables2 2 and and3, 3 , for example)[ 1 ]. In contrast to experimental designs, which seek to test a specific hypothesis through deliberately manipulating the environment (like, for example, in a randomised controlled trial giving a new drug to randomly selected individuals and then comparing outcomes with controls),[ 9 ] the case study approach lends itself well to capturing information on more explanatory ' how ', 'what' and ' why ' questions, such as ' how is the intervention being implemented and received on the ground?'. The case study approach can offer additional insights into what gaps exist in its delivery or why one implementation strategy might be chosen over another. This in turn can help develop or refine theory, as shown in our study of the teaching of patient safety in undergraduate curricula (Table (Table4 4 )[ 6 , 10 ]. Key questions to consider when selecting the most appropriate study design are whether it is desirable or indeed possible to undertake a formal experimental investigation in which individuals and/or organisations are allocated to an intervention or control arm? Or whether the wish is to obtain a more naturalistic understanding of an issue? The former is ideally studied using a controlled experimental design, whereas the latter is more appropriately studied using a case study design.
Case studies may be approached in different ways depending on the epistemological standpoint of the researcher, that is, whether they take a critical (questioning one's own and others' assumptions), interpretivist (trying to understand individual and shared social meanings) or positivist approach (orientating towards the criteria of natural sciences, such as focusing on generalisability considerations) (Table (Table6). 6 ). Whilst such a schema can be conceptually helpful, it may be appropriate to draw on more than one approach in any case study, particularly in the context of conducting health services research. Doolin has, for example, noted that in the context of undertaking interpretative case studies, researchers can usefully draw on a critical, reflective perspective which seeks to take into account the wider social and political environment that has shaped the case[ 11 ].
Example of epistemological approaches that may be used in case study research
How are case studies conducted?
Here, we focus on the main stages of research activity when planning and undertaking a case study; the crucial stages are: defining the case; selecting the case(s); collecting and analysing the data; interpreting data; and reporting the findings.
Defining the case
Carefully formulated research question(s), informed by the existing literature and a prior appreciation of the theoretical issues and setting(s), are all important in appropriately and succinctly defining the case[ 8 , 12 ]. Crucially, each case should have a pre-defined boundary which clarifies the nature and time period covered by the case study (i.e. its scope, beginning and end), the relevant social group, organisation or geographical area of interest to the investigator, the types of evidence to be collected, and the priorities for data collection and analysis (see Table Table7 7 )[ 1 ]. A theory driven approach to defining the case may help generate knowledge that is potentially transferable to a range of clinical contexts and behaviours; using theory is also likely to result in a more informed appreciation of, for example, how and why interventions have succeeded or failed[ 13 ].
Example of a checklist for rating a case study proposal[ 8 ]
For example, in our evaluation of the introduction of electronic health records in English hospitals (Table (Table3), 3 ), we defined our cases as the NHS Trusts that were receiving the new technology[ 5 ]. Our focus was on how the technology was being implemented. However, if the primary research interest had been on the social and organisational dimensions of implementation, we might have defined our case differently as a grouping of healthcare professionals (e.g. doctors and/or nurses). The precise beginning and end of the case may however prove difficult to define. Pursuing this same example, when does the process of implementation and adoption of an electronic health record system really begin or end? Such judgements will inevitably be influenced by a range of factors, including the research question, theory of interest, the scope and richness of the gathered data and the resources available to the research team.
Selecting the case(s)
The decision on how to select the case(s) to study is a very important one that merits some reflection. In an intrinsic case study, the case is selected on its own merits[ 8 ]. The case is selected not because it is representative of other cases, but because of its uniqueness, which is of genuine interest to the researchers. This was, for example, the case in our study of the recruitment of minority ethnic participants into asthma research (Table (Table1) 1 ) as our earlier work had demonstrated the marginalisation of minority ethnic people with asthma, despite evidence of disproportionate asthma morbidity[ 14 , 15 ]. In another example of an intrinsic case study, Hellstrom et al.[ 16 ] studied an elderly married couple living with dementia to explore how dementia had impacted on their understanding of home, their everyday life and their relationships.
For an instrumental case study, selecting a "typical" case can work well[ 8 ]. In contrast to the intrinsic case study, the particular case which is chosen is of less importance than selecting a case that allows the researcher to investigate an issue or phenomenon. For example, in order to gain an understanding of doctors' responses to health policy initiatives, Som undertook an instrumental case study interviewing clinicians who had a range of responsibilities for clinical governance in one NHS acute hospital trust[ 17 ]. Sampling a "deviant" or "atypical" case may however prove even more informative, potentially enabling the researcher to identify causal processes, generate hypotheses and develop theory.
In collective or multiple case studies, a number of cases are carefully selected. This offers the advantage of allowing comparisons to be made across several cases and/or replication. Choosing a "typical" case may enable the findings to be generalised to theory (i.e. analytical generalisation) or to test theory by replicating the findings in a second or even a third case (i.e. replication logic)[ 1 ]. Yin suggests two or three literal replications (i.e. predicting similar results) if the theory is straightforward and five or more if the theory is more subtle. However, critics might argue that selecting 'cases' in this way is insufficiently reflexive and ill-suited to the complexities of contemporary healthcare organisations.
The selected case study site(s) should allow the research team access to the group of individuals, the organisation, the processes or whatever else constitutes the chosen unit of analysis for the study. Access is therefore a central consideration; the researcher needs to come to know the case study site(s) well and to work cooperatively with them. Selected cases need to be not only interesting but also hospitable to the inquiry [ 8 ] if they are to be informative and answer the research question(s). Case study sites may also be pre-selected for the researcher, with decisions being influenced by key stakeholders. For example, our selection of case study sites in the evaluation of the implementation and adoption of electronic health record systems (see Table Table3) 3 ) was heavily influenced by NHS Connecting for Health, the government agency that was responsible for overseeing the National Programme for Information Technology (NPfIT)[ 5 ]. This prominent stakeholder had already selected the NHS sites (through a competitive bidding process) to be early adopters of the electronic health record systems and had negotiated contracts that detailed the deployment timelines.
It is also important to consider in advance the likely burden and risks associated with participation for those who (or the site(s) which) comprise the case study. Of particular importance is the obligation for the researcher to think through the ethical implications of the study (e.g. the risk of inadvertently breaching anonymity or confidentiality) and to ensure that potential participants/participating sites are provided with sufficient information to make an informed choice about joining the study. The outcome of providing this information might be that the emotive burden associated with participation, or the organisational disruption associated with supporting the fieldwork, is considered so high that the individuals or sites decide against participation.
In our example of evaluating implementations of electronic health record systems, given the restricted number of early adopter sites available to us, we sought purposively to select a diverse range of implementation cases among those that were available[ 5 ]. We chose a mixture of teaching, non-teaching and Foundation Trust hospitals, and examples of each of the three electronic health record systems procured centrally by the NPfIT. At one recruited site, it quickly became apparent that access was problematic because of competing demands on that organisation. Recognising the importance of full access and co-operative working for generating rich data, the research team decided not to pursue work at that site and instead to focus on other recruited sites.
Collecting the data
In order to develop a thorough understanding of the case, the case study approach usually involves the collection of multiple sources of evidence, using a range of quantitative (e.g. questionnaires, audits and analysis of routinely collected healthcare data) and more commonly qualitative techniques (e.g. interviews, focus groups and observations). The use of multiple sources of data (data triangulation) has been advocated as a way of increasing the internal validity of a study (i.e. the extent to which the method is appropriate to answer the research question)[ 8 , 18 - 21 ]. An underlying assumption is that data collected in different ways should lead to similar conclusions, and approaching the same issue from different angles can help develop a holistic picture of the phenomenon (Table (Table2 2 )[ 4 ].
Brazier and colleagues used a mixed-methods case study approach to investigate the impact of a cancer care programme[ 22 ]. Here, quantitative measures were collected with questionnaires before, and five months after, the start of the intervention which did not yield any statistically significant results. Qualitative interviews with patients however helped provide an insight into potentially beneficial process-related aspects of the programme, such as greater, perceived patient involvement in care. The authors reported how this case study approach provided a number of contextual factors likely to influence the effectiveness of the intervention and which were not likely to have been obtained from quantitative methods alone.
In collective or multiple case studies, data collection needs to be flexible enough to allow a detailed description of each individual case to be developed (e.g. the nature of different cancer care programmes), before considering the emerging similarities and differences in cross-case comparisons (e.g. to explore why one programme is more effective than another). It is important that data sources from different cases are, where possible, broadly comparable for this purpose even though they may vary in nature and depth.
Analysing, interpreting and reporting case studies
Making sense and offering a coherent interpretation of the typically disparate sources of data (whether qualitative alone or together with quantitative) is far from straightforward. Repeated reviewing and sorting of the voluminous and detail-rich data are integral to the process of analysis. In collective case studies, it is helpful to analyse data relating to the individual component cases first, before making comparisons across cases. Attention needs to be paid to variations within each case and, where relevant, the relationship between different causes, effects and outcomes[ 23 ]. Data will need to be organised and coded to allow the key issues, both derived from the literature and emerging from the dataset, to be easily retrieved at a later stage. An initial coding frame can help capture these issues and can be applied systematically to the whole dataset with the aid of a qualitative data analysis software package.
The Framework approach is a practical approach, comprising of five stages (familiarisation; identifying a thematic framework; indexing; charting; mapping and interpretation) , to managing and analysing large datasets particularly if time is limited, as was the case in our study of recruitment of South Asians into asthma research (Table (Table1 1 )[ 3 , 24 ]. Theoretical frameworks may also play an important role in integrating different sources of data and examining emerging themes. For example, we drew on a socio-technical framework to help explain the connections between different elements - technology; people; and the organisational settings within which they worked - in our study of the introduction of electronic health record systems (Table (Table3 3 )[ 5 ]. Our study of patient safety in undergraduate curricula drew on an evaluation-based approach to design and analysis, which emphasised the importance of the academic, organisational and practice contexts through which students learn (Table (Table4 4 )[ 6 ].
Case study findings can have implications both for theory development and theory testing. They may establish, strengthen or weaken historical explanations of a case and, in certain circumstances, allow theoretical (as opposed to statistical) generalisation beyond the particular cases studied[ 12 ]. These theoretical lenses should not, however, constitute a strait-jacket and the cases should not be "forced to fit" the particular theoretical framework that is being employed.
When reporting findings, it is important to provide the reader with enough contextual information to understand the processes that were followed and how the conclusions were reached. In a collective case study, researchers may choose to present the findings from individual cases separately before amalgamating across cases. Care must be taken to ensure the anonymity of both case sites and individual participants (if agreed in advance) by allocating appropriate codes or withholding descriptors. In the example given in Table Table3, 3 , we decided against providing detailed information on the NHS sites and individual participants in order to avoid the risk of inadvertent disclosure of identities[ 5 , 25 ].
What are the potential pitfalls and how can these be avoided?
The case study approach is, as with all research, not without its limitations. When investigating the formal and informal ways undergraduate students learn about patient safety (Table (Table4), 4 ), for example, we rapidly accumulated a large quantity of data. The volume of data, together with the time restrictions in place, impacted on the depth of analysis that was possible within the available resources. This highlights a more general point of the importance of avoiding the temptation to collect as much data as possible; adequate time also needs to be set aside for data analysis and interpretation of what are often highly complex datasets.
Case study research has sometimes been criticised for lacking scientific rigour and providing little basis for generalisation (i.e. producing findings that may be transferable to other settings)[ 1 ]. There are several ways to address these concerns, including: the use of theoretical sampling (i.e. drawing on a particular conceptual framework); respondent validation (i.e. participants checking emerging findings and the researcher's interpretation, and providing an opinion as to whether they feel these are accurate); and transparency throughout the research process (see Table Table8 8 )[ 8 , 18 - 21 , 23 , 26 ]. Transparency can be achieved by describing in detail the steps involved in case selection, data collection, the reasons for the particular methods chosen, and the researcher's background and level of involvement (i.e. being explicit about how the researcher has influenced data collection and interpretation). Seeking potential, alternative explanations, and being explicit about how interpretations and conclusions were reached, help readers to judge the trustworthiness of the case study report. Stake provides a critique checklist for a case study report (Table (Table9 9 )[ 8 ].
Potential pitfalls and mitigating actions when undertaking case study research
Stake's checklist for assessing the quality of a case study report[ 8 ]
Conclusions
The case study approach allows, amongst other things, critical events, interventions, policy developments and programme-based service reforms to be studied in detail in a real-life context. It should therefore be considered when an experimental design is either inappropriate to answer the research questions posed or impossible to undertake. Considering the frequency with which implementations of innovations are now taking place in healthcare settings and how well the case study approach lends itself to in-depth, complex health service research, we believe this approach should be more widely considered by researchers. Though inherently challenging, the research case study can, if carefully conceptualised and thoughtfully undertaken and reported, yield powerful insights into many important aspects of health and healthcare delivery.
Competing interests
The authors declare that they have no competing interests.
Authors' contributions
AS conceived this article. SC, KC and AR wrote this paper with GH, AA and AS all commenting on various drafts. SC and AS are guarantors.
Pre-publication history
The pre-publication history for this paper can be accessed here:
http://www.biomedcentral.com/1471-2288/11/100/prepub
Acknowledgements
We are grateful to the participants and colleagues who contributed to the individual case studies that we have drawn on. This work received no direct funding, but it has been informed by projects funded by Asthma UK, the NHS Service Delivery Organisation, NHS Connecting for Health Evaluation Programme, and Patient Safety Research Portfolio. We would also like to thank the expert reviewers for their insightful and constructive feedback. Our thanks are also due to Dr. Allison Worth who commented on an earlier draft of this manuscript.
- Yin RK. Case study research, design and method. 4. London: Sage Publications Ltd.; 2009. [ Google Scholar ]
- Keen J, Packwood T. Qualitative research; case study evaluation. BMJ. 1995; 311 :444–446. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Sheikh A, Halani L, Bhopal R, Netuveli G, Partridge M, Car J. et al. Facilitating the Recruitment of Minority Ethnic People into Research: Qualitative Case Study of South Asians and Asthma. PLoS Med. 2009; 6 (10):1–11. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Pinnock H, Huby G, Powell A, Kielmann T, Price D, Williams S, The process of planning, development and implementation of a General Practitioner with a Special Interest service in Primary Care Organisations in England and Wales: a comparative prospective case study. Report for the National Co-ordinating Centre for NHS Service Delivery and Organisation R&D (NCCSDO) 2008. http://www.sdo.nihr.ac.uk/files/project/99-final-report.pdf
- Robertson A, Cresswell K, Takian A, Petrakaki D, Crowe S, Cornford T. et al. Prospective evaluation of the implementation and adoption of NHS Connecting for Health's national electronic health record in secondary care in England: interim findings. BMJ. 2010; 41 :c4564. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Pearson P, Steven A, Howe A, Sheikh A, Ashcroft D, Smith P. the Patient Safety Education Study Group. Learning about patient safety: organisational context and culture in the education of healthcare professionals. J Health Serv Res Policy. 2010; 15 :4–10. doi: 10.1258/jhsrp.2009.009052. [ PubMed ] [ CrossRef ] [ Google Scholar ]
- van Harten WH, Casparie TF, Fisscher OA. The evaluation of the introduction of a quality management system: a process-oriented case study in a large rehabilitation hospital. Health Policy. 2002; 60 (1):17–37. doi: 10.1016/S0168-8510(01)00187-7. [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Stake RE. The art of case study research. London: Sage Publications Ltd.; 1995. [ Google Scholar ]
- Sheikh A, Smeeth L, Ashcroft R. Randomised controlled trials in primary care: scope and application. Br J Gen Pract. 2002; 52 (482):746–51. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- King G, Keohane R, Verba S. Designing Social Inquiry. Princeton: Princeton University Press; 1996. [ Google Scholar ]
- Doolin B. Information technology as disciplinary technology: being critical in interpretative research on information systems. Journal of Information Technology. 1998; 13 :301–311. doi: 10.1057/jit.1998.8. [ CrossRef ] [ Google Scholar ]
- George AL, Bennett A. Case studies and theory development in the social sciences. Cambridge, MA: MIT Press; 2005. [ Google Scholar ]
- Eccles M. the Improved Clinical Effectiveness through Behavioural Research Group (ICEBeRG) Designing theoretically-informed implementation interventions. Implementation Science. 2006; 1 :1–8. doi: 10.1186/1748-5908-1-1. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Netuveli G, Hurwitz B, Levy M, Fletcher M, Barnes G, Durham SR, Sheikh A. Ethnic variations in UK asthma frequency, morbidity, and health-service use: a systematic review and meta-analysis. Lancet. 2005; 365 (9456):312–7. [ PubMed ] [ Google Scholar ]
- Sheikh A, Panesar SS, Lasserson T, Netuveli G. Recruitment of ethnic minorities to asthma studies. Thorax. 2004; 59 (7):634. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Hellström I, Nolan M, Lundh U. 'We do things together': A case study of 'couplehood' in dementia. Dementia. 2005; 4 :7–22. doi: 10.1177/1471301205049188. [ CrossRef ] [ Google Scholar ]
- Som CV. Nothing seems to have changed, nothing seems to be changing and perhaps nothing will change in the NHS: doctors' response to clinical governance. International Journal of Public Sector Management. 2005; 18 :463–477. doi: 10.1108/09513550510608903. [ CrossRef ] [ Google Scholar ]
- Lincoln Y, Guba E. Naturalistic inquiry. Newbury Park: Sage Publications; 1985. [ Google Scholar ]
- Barbour RS. Checklists for improving rigour in qualitative research: a case of the tail wagging the dog? BMJ. 2001; 322 :1115–1117. doi: 10.1136/bmj.322.7294.1115. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Mays N, Pope C. Qualitative research in health care: Assessing quality in qualitative research. BMJ. 2000; 320 :50–52. doi: 10.1136/bmj.320.7226.50. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Mason J. Qualitative researching. London: Sage; 2002. [ Google Scholar ]
- Brazier A, Cooke K, Moravan V. Using Mixed Methods for Evaluating an Integrative Approach to Cancer Care: A Case Study. Integr Cancer Ther. 2008; 7 :5–17. doi: 10.1177/1534735407313395. [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Miles MB, Huberman M. Qualitative data analysis: an expanded sourcebook. 2. CA: Sage Publications Inc.; 1994. [ Google Scholar ]
- Pope C, Ziebland S, Mays N. Analysing qualitative data. Qualitative research in health care. BMJ. 2000; 320 :114–116. doi: 10.1136/bmj.320.7227.114. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Cresswell KM, Worth A, Sheikh A. Actor-Network Theory and its role in understanding the implementation of information technology developments in healthcare. BMC Med Inform Decis Mak. 2010; 10 (1):67. doi: 10.1186/1472-6947-10-67. [ PMC free article ] [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Malterud K. Qualitative research: standards, challenges, and guidelines. Lancet. 2001; 358 :483–488. doi: 10.1016/S0140-6736(01)05627-6. [ PubMed ] [ CrossRef ] [ Google Scholar ]
- Yin R. Case study research: design and methods. 2. Thousand Oaks, CA: Sage Publishing; 1994. [ Google Scholar ]
- Yin R. Enhancing the quality of case studies in health services research. Health Serv Res. 1999; 34 :1209–1224. [ PMC free article ] [ PubMed ] [ Google Scholar ]
- Green J, Thorogood N. Qualitative methods for health research. 2. Los Angeles: Sage; 2009. [ Google Scholar ]
- Howcroft D, Trauth E. Handbook of Critical Information Systems Research, Theory and Application. Cheltenham, UK: Northampton, MA, USA: Edward Elgar; 2005. [ Google Scholar ]
- Blakie N. Approaches to Social Enquiry. Cambridge: Polity Press; 1993. [ Google Scholar ]
- Doolin B. Power and resistance in the implementation of a medical management information system. Info Systems J. 2004; 14 :343–362. doi: 10.1111/j.1365-2575.2004.00176.x. [ CrossRef ] [ Google Scholar ]
- Bloomfield BP, Best A. Management consultants: systems development, power and the translation of problems. Sociological Review. 1992; 40 :533–560. [ Google Scholar ]
- Shanks G, Parr A. Proceedings of the European Conference on Information Systems. Naples; 2003. Positivist, single case study research in information systems: A critical analysis. [ Google Scholar ]
- Bipolar Disorder
- Race and Identity
- Stress Management
- Brain Health
- Relationships
- Online Therapy
- History and Biographies
- Student Resources
- Sleep and Dreaming
- Self-Improvement
- Mental Strength
- Family & Relationships
- Anxiety & Depression
- Coronavirus
- Mental Health
- Verywell Mind Insights
- The Winter Issue
- Editorial Process
- Meet Our Review Board
- Crisis Support
What Is a Case Study?
An in-depth study of one person, group, or event
Kendra Cherry, MS, is an author and educational consultant focused on helping students learn about psychology.
:max_bytes(150000):strip_icc():format(webp)/IMG_9791-89504ab694d54b66bbd72cb84ffb860e.jpg "what is the purpose of a case study in research")
Cara Lustik is a fact-checker and copywriter.
:max_bytes(150000):strip_icc():format(webp)/Cara-Lustik-1000-77abe13cf6c14a34a58c2a0ffb7297da.jpg "what is the purpose of a case study in research")
Verywell / Colleen Tighe
Benefits and Limitations
Types of case studies, how to write a case study.
A case study is an in-depth study of one person, group, or event. In a case study, nearly every aspect of the subject's life and history is analyzed to seek patterns and causes of behavior. Case studies can be used in various fields, including psychology, medicine, education, anthropology, political science, and social work.
The purpose of a case study is to learn as much as possible about an individual or group so that the information can be generalized to many others. Unfortunately, case studies tend to be highly subjective, and it is sometimes difficult to generalize results to a larger population.
While case studies focus on a single individual or group, they follow a format similar to other types of psychology writing. If you are writing a case study, it is important to follow the rules of APA format .
A case study can have both strengths and weaknesses. Researchers must consider these pros and cons before deciding if this type of study is appropriate for their needs.
One of the greatest advantages of a case study is that it allows researchers to investigate things that are often difficult to impossible to replicate in a lab. Some other benefits of a case study:
- Allows researchers to collect a great deal of information
- Give researchers the chance to collect information on rare or unusual cases
- Permits researchers to develop hypotheses that can be explored in experimental research
On the negative side, a case study:
- Cannot necessarily be generalized to the larger population
- Cannot demonstrate cause and effect
- May not be scientifically rigorous
- Can lead to bias
Researchers may choose to perform a case study if they are interested in exploring a unique or recently discovered phenomenon. The insights gained from such research can help the researchers develop additional ideas and study questions that might be explored in future studies.
However, it is important to remember that the insights gained from case studies cannot be used to determine cause and effect relationships between variables. However, case studies may be used to develop hypotheses that can then be addressed in experimental research.
Case Study Examples
There have been a number of notable case studies in the history of psychology. Much of Freud's work and theories were developed through the use of individual case studies. Some great examples of case studies in psychology include:
- Anna O : Anna O. was a pseudonym of a woman named Bertha Pappenheim, a patient of a physician named Josef Breuer. While she was never a patient of Freud's, Freud and Breuer discussed her case extensively. The woman was experiencing symptoms of a condition that was then known as hysteria and found that talking about her problems helped relieve her symptoms. Her case played an important part in the development of talk therapy as an approach to mental health treatment.
- Phineas Gage : Phineas Gage was a railroad employee who experienced a terrible accident in which an explosion sent a metal rod through his skull, damaging important portions of his brain. Gage recovered from his accident but was left with serious changes in both personality and behavior.
- Genie : Genie was a young girl subjected to horrific abuse and isolation. The case study of Genie allowed researchers to study whether language could be taught even after critical periods for language development had been missed. Her case also served as an example of how scientific research may interfere with treatment and lead to further abuse of vulnerable individuals.
Such cases demonstrate how case research can be used to study things that researchers could not replicate in experimental settings. In Genie's case, her horrific abuse had denied her the opportunity to learn language at critical points in her development.
This is clearly not something that researchers could ethically replicate, but conducting a case study on Genie allowed researchers the chance to study phenomena that are otherwise impossible to reproduce.
There are a few different types of case studies that psychologists and other researchers might utilize:
- Collective case studies : These involve studying a group of individuals. Researchers might study a group of people in a certain setting or look at an entire community. For example, psychologists might explore how access to resources in a community has affected the collective mental well-being of those living there.
- Descriptive case studies : These involve starting with a descriptive theory. The subjects are then observed, and the information gathered is compared to the pre-existing theory.
- Explanatory case studies : These are often used to do causal investigations. In other words, researchers are interested in looking at factors that may have caused certain things to occur.
- Exploratory case studies : These are sometimes used as a prelude to further, more in-depth research. This allows researchers to gather more information before developing their research questions and hypotheses .
- Instrumental case studies : These occur when the individual or group allows researchers to understand more than what is initially obvious to observers.
- Intrinsic case studies : This type of case study is when the researcher has a personal interest in the case. Jean Piaget's observations of his own children are good examples of how an intrinsic cast study can contribute to the development of a psychological theory.
The three main case study types often used are intrinsic, instrumental, and collective. Intrinsic case studies are useful for learning about unique cases. Instrumental case studies help look at an individual to learn more about a broader issue. A collective case study can be useful for looking at several cases simultaneously.
The type of case study that psychology researchers utilize depends on the unique characteristics of the situation as well as the case itself.
There are also different methods that can be used to conduct a case study, including prospective and retrospective case study methods.
Prospective case study methods are those in which an individual or group of people is observed in order to determine outcomes. For example, a group of individuals might be watched over an extended period of time to observe the progression of a particular disease.
Retrospective case study methods involve looking at historical information. For example, researchers might start with an outcome, such as a disease, and then work their way backward to look at information about the individual's life to determine risk factors that may have contributed to the onset of the illness.
Where to Find Data
There are a number of different sources and methods that researchers can use to gather information about an individual or group. Six major sources that have been identified by researchers are:
- Archival records : Census records, survey records, and name lists are examples of archival records.
- Direct observation : This strategy involves observing the subject, often in a natural setting . While an individual observer is sometimes used, it is more common to utilize a group of observers.
- Documents : Letters, newspaper articles, administrative records, etc., are the types of documents often used as sources.
- Interviews : Interviews are one of the most important methods for gathering information in case studies. An interview can involve structured survey questions or more open-ended questions.
- Participant observation : When the researcher serves as a participant in events and observes the actions and outcomes, it is called participant observation.
- Physical artifacts : Tools, objects, instruments, and other artifacts are often observed during a direct observation of the subject.
Section 1: A Case History
This section will have the following structure and content:
Background information : The first section of your paper will present your client's background. Include factors such as age, gender, work, health status, family mental health history, family and social relationships, drug and alcohol history, life difficulties, goals, and coping skills and weaknesses.
Description of the presenting problem : In the next section of your case study, you will describe the problem or symptoms that the client presented with.
Describe any physical, emotional, or sensory symptoms reported by the client. Thoughts, feelings, and perceptions related to the symptoms should also be noted. Any screening or diagnostic assessments that are used should also be described in detail and all scores reported.
Your diagnosis : Provide your diagnosis and give the appropriate Diagnostic and Statistical Manual code. Explain how you reached your diagnosis, how the client's symptoms fit the diagnostic criteria for the disorder(s), or any possible difficulties in reaching a diagnosis.
Section 2: Treatment Plan
This portion of the paper will address the chosen treatment for the condition. This might also include the theoretical basis for the chosen treatment or any other evidence that might exist to support why this approach was chosen.
- Cognitive behavioral approach : Explain how a cognitive behavioral therapist would approach treatment. Offer background information on cognitive behavioral therapy and describe the treatment sessions, client response, and outcome of this type of treatment. Make note of any difficulties or successes encountered by your client during treatment.
- Humanistic approach : Describe a humanistic approach that could be used to treat your client, such as client-centered therapy . Provide information on the type of treatment you chose, the client's reaction to the treatment, and the end result of this approach. Explain why the treatment was successful or unsuccessful.
- Psychoanalytic approach : Describe how a psychoanalytic therapist would view the client's problem. Provide some background on the psychoanalytic approach and cite relevant references. Explain how psychoanalytic therapy would be used to treat the client, how the client would respond to therapy, and the effectiveness of this treatment approach.
- Pharmacological approach : If treatment primarily involves the use of medications, explain which medications were used and why. Provide background on the effectiveness of these medications and how monotherapy may compare with an approach that combines medications with therapy or other treatments.
This section of a case study should also include information about the treatment goals, process, and outcomes.
When you are writing a case study, you should also include a section where you discuss the case study itself, including the strengths and limitiations of the study. You should note how the findings of your case study might support previous research.
In your discussion section, you should also describe some of the implications of your case study. What ideas or findings might require further exploration? How might researchers go about exploring some of these questions in additional studies?
Here are a few additional pointers to keep in mind when formatting your case study:
- Never refer to the subject of your case study as "the client." Instead, their name or a pseudonym.
- Read examples of case studies to gain an idea about the style and format.
- Remember to use APA format when citing references .
A Word From Verywell
Case studies can be a useful research tool, but they need to be used wisely. In many cases, they are best utilized in situations where conducting an experiment would be difficult or impossible. They are helpful for looking at unique situations and allow researchers to gather a great deal of information about a specific individual or group of people.
If you have been directed to write a case study for a psychology course, be sure to check with your instructor for any specific guidelines that you are required to follow. If you are writing your case study for professional publication, be sure to check with the publisher for their specific guidelines for submitting a case study.
Simply Psychology. Case Study Method .
Crowe S, Cresswell K, Robertson A, Huby G, Avery A, Sheikh A. The case study approach . BMC Med Res Methodol . 2011 Jun 27;11:100. doi:10.1186/1471-2288-11-100
Gagnon, Yves-Chantal. The Case Study as Research Method: A Practical Handbook . Canada, Chicago Review Press Incorporated DBA Independent Pub Group, 2010.
Yin, Robert K. Case Study Research and Applications: Design and Methods . United States, SAGE Publications, 2017.
By Kendra Cherry Kendra Cherry, MS, is an author and educational consultant focused on helping students learn about psychology.
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.
You are using an outdated browser. Please upgrade your browser to improve your experience.
Search form
- Volunteering
- Stay updated
- News and events
- The importance of case studies in social research
Like children in a sweetshop, researchers are often spoilt for choice when it comes to determining which tools to use to address a research question. This includes an array of quantitative and qualitative research tools, ranging from desk-based literature reviews to in-depth case studies. Given the time and cost restraints of many projects the more in-depth methods are often perceived as time consuming and frequently dismissed. Based on my experience, here are my thoughts on the value and challenges of including case studies in social research.
Case studies are an in-depth investigation of one particular individual, group, time-period or event. They encompass a range of qualitative and quantitative research tools to investigate underlying principles of an occurrence within a real-life context.
For example, last year, Changeworks was commissioned to undertake research for the Joseph Rowntree Foundation with the purpose of exploring whether or not district heating in UK social housing is delivering against its affordability and sustainability goals. The project gave us the opportunity to use eight case studies to support a wider literature review, a social housing provider survey and stakeholder interviews.
- Comprehensive . The most significant benefit of case studies is that they enable a holistic review. Unlike standalone research techniques which give more of a snapshot, eg surveys, a case study offers the opportunity for a researcher to use a range of tools on one subject. This gives time and space to build a detailed understanding of the topic, establishing a sound platform from which to explore the factors influencing the case study in greater detail.
- Reducing bias . Case studies capture a range of perspectives, as opposed to the single view of an individual you get with a survey response or interview. This gives the opportunity to gain a greater understanding of the subject in hand and reduces the potential for any bias, by diluting the agenda of a particular individual. The methodology for the district heating case studies included face-to-face interviews with up to five members of staff from relevant social housing departments and external organisations where third party management organisations were used. The methodology also featured in-depth technical and financial analysis and a focus group with residents from each of the case study schemes.
- Wider relevance . A common criticism of the case study is that the findings can’t be generalised. However, we’ve found when they’re part of broader research a case study can look to explore common problems in greater detail. In the district heating research we used the broader background research to identify areas of particular interest and then used the case studies to further investigate the causes and impacts. Furthermore, the case study participants were carefully selected to ensure a good spread of locations, technologies and management arrangements.
- Permissions . In social research, maintaining participants’ anonymity helps to provide a true picture of what is happening. Studies have shown that participants are more open with the research team in situations where they are confident that their identity will not be disclosed 1 . However maintaining anonymity can be challenging given the detailed nature of the case study. For in-depth case studies it may be appropriate to seek confirmation that the lead participant agrees that the material is anonymous and accurate, enabling confidence on both the part of the researcher and the participant. However the process of gaining permission can take time and result in additional iterations of the published research.
- Time . Case studies can be time consuming. Planning multiple interviews, waiting to receive data and possibly co-ordinating focus groups can take a considerable amount of time. Especially if you are relying on a case study participant who is often acting in a voluntary capacity and busy fulfilling their day to day tasks. Yet these issues can be overcome by offering participants incentives, outlining what is required from the participant at the outset and sending notification of deadlines well in advance.
I believe that case studies enable a researcher to gain a more detailed, un-biased understanding of a complex situation, through the use of a range of research tools. This real-life view, places the research organisation in a stronger position to confidently recommend practical solutions to challenges. While there are some difficulties associated with the delivery of case studies, these can be overcome through forward planning, background research and informed participant selection.
If you’re interested in commissioning a piece of research, or to discuss how research can help inform your project, please get in touch with me. You can also read our report to find out more about the case studies that featured in our latest district heating research.
Lauren
Lauren Salmon Changeworks Researcher
- Ong, A. D. and Weiss, D. J. (2000), The Impact of Anonymity on Responses to Sensitive Questions1. Journal of Applied Social Psychology, 30: 1691–1708. doi:10.1111/j.1559-1816.2000.tb02462.x
View the discussion thread.
- News Archive
- FAQs - Air source heat pumps
Sign up to our news, insights and events on low carbon living and working
Your data : We will store your information with your consent only for the purposes of sending you the information you’d like to hear from us. We will not share your details with any third parties. We will store your data safely and indefinitely or you can unsubscribe at any time. More information on how we protect and use the details you give us.
- Open Access
- Published: 27 June 2011
The case study approach
- Sarah Crowe 1 ,
- Kathrin Cresswell 2 ,
- Ann Robertson 2 ,
- Guro Huby 3 ,
- Anthony Avery 1 &
- Aziz Sheikh 2
BMC Medical Research Methodology volume 11 , Article number: 100 ( 2011 ) Cite this article
The case study approach allows in-depth, multi-faceted explorations of complex issues in their real-life settings. The value of the case study approach is well recognised in the fields of business, law and policy, but somewhat less so in health services research. Based on our experiences of conducting several health-related case studies, we reflect on the different types of case study design, the specific research questions this approach can help answer, the data sources that tend to be used, and the particular advantages and disadvantages of employing this methodological approach. The paper concludes with key pointers to aid those designing and appraising proposals for conducting case study research, and a checklist to help readers assess the quality of case study reports.
Peer Review reports
Introduction
The case study approach is particularly useful to employ when there is a need to obtain an in-depth appreciation of an issue, event or phenomenon of interest, in its natural real-life context. Our aim in writing this piece is to provide insights into when to consider employing this approach and an overview of key methodological considerations in relation to the design, planning, analysis, interpretation and reporting of case studies.
The illustrative 'grand round', 'case report' and 'case series' have a long tradition in clinical practice and research. Presenting detailed critiques, typically of one or more patients, aims to provide insights into aspects of the clinical case and, in doing so, illustrate broader lessons that may be learnt. In research, the conceptually-related case study approach can be used, for example, to describe in detail a patient's episode of care, explore professional attitudes to and experiences of a new policy initiative or service development or more generally to 'investigate contemporary phenomena within its real-life context' [ 1 ]. Based on our experiences of conducting a range of case studies, we reflect on when to consider using this approach, discuss the key steps involved and illustrate, with examples, some of the practical challenges of attaining an in-depth understanding of a 'case' as an integrated whole. In keeping with previously published work, we acknowledge the importance of theory to underpin the design, selection, conduct and interpretation of case studies[ 2 ]. In so doing, we make passing reference to the different epistemological approaches used in case study research by key theoreticians and methodologists in this field of enquiry.
This paper is structured around the following main questions: What is a case study? What are case studies used for? How are case studies conducted? What are the potential pitfalls and how can these be avoided? We draw in particular on four of our own recently published examples of case studies (see Tables 1 , 2 , 3 and 4 ) and those of others to illustrate our discussion[ 3 – 7 ].
What is a case study?
A case study is a research approach that is used to generate an in-depth, multi-faceted understanding of a complex issue in its real-life context. It is an established research design that is used extensively in a wide variety of disciplines, particularly in the social sciences. A case study can be defined in a variety of ways (Table 5 ), the central tenet being the need to explore an event or phenomenon in depth and in its natural context. It is for this reason sometimes referred to as a "naturalistic" design; this is in contrast to an "experimental" design (such as a randomised controlled trial) in which the investigator seeks to exert control over and manipulate the variable(s) of interest.
Stake's work has been particularly influential in defining the case study approach to scientific enquiry. He has helpfully characterised three main types of case study: intrinsic , instrumental and collective [ 8 ]. An intrinsic case study is typically undertaken to learn about a unique phenomenon. The researcher should define the uniqueness of the phenomenon, which distinguishes it from all others. In contrast, the instrumental case study uses a particular case (some of which may be better than others) to gain a broader appreciation of an issue or phenomenon. The collective case study involves studying multiple cases simultaneously or sequentially in an attempt to generate a still broader appreciation of a particular issue.
These are however not necessarily mutually exclusive categories. In the first of our examples (Table 1 ), we undertook an intrinsic case study to investigate the issue of recruitment of minority ethnic people into the specific context of asthma research studies, but it developed into a instrumental case study through seeking to understand the issue of recruitment of these marginalised populations more generally, generating a number of the findings that are potentially transferable to other disease contexts[ 3 ]. In contrast, the other three examples (see Tables 2 , 3 and 4 ) employed collective case study designs to study the introduction of workforce reconfiguration in primary care, the implementation of electronic health records into hospitals, and to understand the ways in which healthcare students learn about patient safety considerations[ 4 – 6 ]. Although our study focusing on the introduction of General Practitioners with Specialist Interests (Table 2 ) was explicitly collective in design (four contrasting primary care organisations were studied), is was also instrumental in that this particular professional group was studied as an exemplar of the more general phenomenon of workforce redesign[ 4 ].
What are case studies used for?
According to Yin, case studies can be used to explain, describe or explore events or phenomena in the everyday contexts in which they occur[ 1 ]. These can, for example, help to understand and explain causal links and pathways resulting from a new policy initiative or service development (see Tables 2 and 3 , for example)[ 1 ]. In contrast to experimental designs, which seek to test a specific hypothesis through deliberately manipulating the environment (like, for example, in a randomised controlled trial giving a new drug to randomly selected individuals and then comparing outcomes with controls),[ 9 ] the case study approach lends itself well to capturing information on more explanatory ' how ', 'what' and ' why ' questions, such as ' how is the intervention being implemented and received on the ground?'. The case study approach can offer additional insights into what gaps exist in its delivery or why one implementation strategy might be chosen over another. This in turn can help develop or refine theory, as shown in our study of the teaching of patient safety in undergraduate curricula (Table 4 )[ 6 , 10 ]. Key questions to consider when selecting the most appropriate study design are whether it is desirable or indeed possible to undertake a formal experimental investigation in which individuals and/or organisations are allocated to an intervention or control arm? Or whether the wish is to obtain a more naturalistic understanding of an issue? The former is ideally studied using a controlled experimental design, whereas the latter is more appropriately studied using a case study design.
Case studies may be approached in different ways depending on the epistemological standpoint of the researcher, that is, whether they take a critical (questioning one's own and others' assumptions), interpretivist (trying to understand individual and shared social meanings) or positivist approach (orientating towards the criteria of natural sciences, such as focusing on generalisability considerations) (Table 6 ). Whilst such a schema can be conceptually helpful, it may be appropriate to draw on more than one approach in any case study, particularly in the context of conducting health services research. Doolin has, for example, noted that in the context of undertaking interpretative case studies, researchers can usefully draw on a critical, reflective perspective which seeks to take into account the wider social and political environment that has shaped the case[ 11 ].
How are case studies conducted?
Here, we focus on the main stages of research activity when planning and undertaking a case study; the crucial stages are: defining the case; selecting the case(s); collecting and analysing the data; interpreting data; and reporting the findings.
Defining the case
Carefully formulated research question(s), informed by the existing literature and a prior appreciation of the theoretical issues and setting(s), are all important in appropriately and succinctly defining the case[ 8 , 12 ]. Crucially, each case should have a pre-defined boundary which clarifies the nature and time period covered by the case study (i.e. its scope, beginning and end), the relevant social group, organisation or geographical area of interest to the investigator, the types of evidence to be collected, and the priorities for data collection and analysis (see Table 7 )[ 1 ]. A theory driven approach to defining the case may help generate knowledge that is potentially transferable to a range of clinical contexts and behaviours; using theory is also likely to result in a more informed appreciation of, for example, how and why interventions have succeeded or failed[ 13 ].
For example, in our evaluation of the introduction of electronic health records in English hospitals (Table 3 ), we defined our cases as the NHS Trusts that were receiving the new technology[ 5 ]. Our focus was on how the technology was being implemented. However, if the primary research interest had been on the social and organisational dimensions of implementation, we might have defined our case differently as a grouping of healthcare professionals (e.g. doctors and/or nurses). The precise beginning and end of the case may however prove difficult to define. Pursuing this same example, when does the process of implementation and adoption of an electronic health record system really begin or end? Such judgements will inevitably be influenced by a range of factors, including the research question, theory of interest, the scope and richness of the gathered data and the resources available to the research team.
Selecting the case(s)
The decision on how to select the case(s) to study is a very important one that merits some reflection. In an intrinsic case study, the case is selected on its own merits[ 8 ]. The case is selected not because it is representative of other cases, but because of its uniqueness, which is of genuine interest to the researchers. This was, for example, the case in our study of the recruitment of minority ethnic participants into asthma research (Table 1 ) as our earlier work had demonstrated the marginalisation of minority ethnic people with asthma, despite evidence of disproportionate asthma morbidity[ 14 , 15 ]. In another example of an intrinsic case study, Hellstrom et al.[ 16 ] studied an elderly married couple living with dementia to explore how dementia had impacted on their understanding of home, their everyday life and their relationships.
For an instrumental case study, selecting a "typical" case can work well[ 8 ]. In contrast to the intrinsic case study, the particular case which is chosen is of less importance than selecting a case that allows the researcher to investigate an issue or phenomenon. For example, in order to gain an understanding of doctors' responses to health policy initiatives, Som undertook an instrumental case study interviewing clinicians who had a range of responsibilities for clinical governance in one NHS acute hospital trust[ 17 ]. Sampling a "deviant" or "atypical" case may however prove even more informative, potentially enabling the researcher to identify causal processes, generate hypotheses and develop theory.
In collective or multiple case studies, a number of cases are carefully selected. This offers the advantage of allowing comparisons to be made across several cases and/or replication. Choosing a "typical" case may enable the findings to be generalised to theory (i.e. analytical generalisation) or to test theory by replicating the findings in a second or even a third case (i.e. replication logic)[ 1 ]. Yin suggests two or three literal replications (i.e. predicting similar results) if the theory is straightforward and five or more if the theory is more subtle. However, critics might argue that selecting 'cases' in this way is insufficiently reflexive and ill-suited to the complexities of contemporary healthcare organisations.
The selected case study site(s) should allow the research team access to the group of individuals, the organisation, the processes or whatever else constitutes the chosen unit of analysis for the study. Access is therefore a central consideration; the researcher needs to come to know the case study site(s) well and to work cooperatively with them. Selected cases need to be not only interesting but also hospitable to the inquiry [ 8 ] if they are to be informative and answer the research question(s). Case study sites may also be pre-selected for the researcher, with decisions being influenced by key stakeholders. For example, our selection of case study sites in the evaluation of the implementation and adoption of electronic health record systems (see Table 3 ) was heavily influenced by NHS Connecting for Health, the government agency that was responsible for overseeing the National Programme for Information Technology (NPfIT)[ 5 ]. This prominent stakeholder had already selected the NHS sites (through a competitive bidding process) to be early adopters of the electronic health record systems and had negotiated contracts that detailed the deployment timelines.
It is also important to consider in advance the likely burden and risks associated with participation for those who (or the site(s) which) comprise the case study. Of particular importance is the obligation for the researcher to think through the ethical implications of the study (e.g. the risk of inadvertently breaching anonymity or confidentiality) and to ensure that potential participants/participating sites are provided with sufficient information to make an informed choice about joining the study. The outcome of providing this information might be that the emotive burden associated with participation, or the organisational disruption associated with supporting the fieldwork, is considered so high that the individuals or sites decide against participation.
In our example of evaluating implementations of electronic health record systems, given the restricted number of early adopter sites available to us, we sought purposively to select a diverse range of implementation cases among those that were available[ 5 ]. We chose a mixture of teaching, non-teaching and Foundation Trust hospitals, and examples of each of the three electronic health record systems procured centrally by the NPfIT. At one recruited site, it quickly became apparent that access was problematic because of competing demands on that organisation. Recognising the importance of full access and co-operative working for generating rich data, the research team decided not to pursue work at that site and instead to focus on other recruited sites.
Collecting the data
In order to develop a thorough understanding of the case, the case study approach usually involves the collection of multiple sources of evidence, using a range of quantitative (e.g. questionnaires, audits and analysis of routinely collected healthcare data) and more commonly qualitative techniques (e.g. interviews, focus groups and observations). The use of multiple sources of data (data triangulation) has been advocated as a way of increasing the internal validity of a study (i.e. the extent to which the method is appropriate to answer the research question)[ 8 , 18 – 21 ]. An underlying assumption is that data collected in different ways should lead to similar conclusions, and approaching the same issue from different angles can help develop a holistic picture of the phenomenon (Table 2 )[ 4 ].
Brazier and colleagues used a mixed-methods case study approach to investigate the impact of a cancer care programme[ 22 ]. Here, quantitative measures were collected with questionnaires before, and five months after, the start of the intervention which did not yield any statistically significant results. Qualitative interviews with patients however helped provide an insight into potentially beneficial process-related aspects of the programme, such as greater, perceived patient involvement in care. The authors reported how this case study approach provided a number of contextual factors likely to influence the effectiveness of the intervention and which were not likely to have been obtained from quantitative methods alone.
In collective or multiple case studies, data collection needs to be flexible enough to allow a detailed description of each individual case to be developed (e.g. the nature of different cancer care programmes), before considering the emerging similarities and differences in cross-case comparisons (e.g. to explore why one programme is more effective than another). It is important that data sources from different cases are, where possible, broadly comparable for this purpose even though they may vary in nature and depth.
Analysing, interpreting and reporting case studies
Making sense and offering a coherent interpretation of the typically disparate sources of data (whether qualitative alone or together with quantitative) is far from straightforward. Repeated reviewing and sorting of the voluminous and detail-rich data are integral to the process of analysis. In collective case studies, it is helpful to analyse data relating to the individual component cases first, before making comparisons across cases. Attention needs to be paid to variations within each case and, where relevant, the relationship between different causes, effects and outcomes[ 23 ]. Data will need to be organised and coded to allow the key issues, both derived from the literature and emerging from the dataset, to be easily retrieved at a later stage. An initial coding frame can help capture these issues and can be applied systematically to the whole dataset with the aid of a qualitative data analysis software package.
The Framework approach is a practical approach, comprising of five stages (familiarisation; identifying a thematic framework; indexing; charting; mapping and interpretation) , to managing and analysing large datasets particularly if time is limited, as was the case in our study of recruitment of South Asians into asthma research (Table 1 )[ 3 , 24 ]. Theoretical frameworks may also play an important role in integrating different sources of data and examining emerging themes. For example, we drew on a socio-technical framework to help explain the connections between different elements - technology; people; and the organisational settings within which they worked - in our study of the introduction of electronic health record systems (Table 3 )[ 5 ]. Our study of patient safety in undergraduate curricula drew on an evaluation-based approach to design and analysis, which emphasised the importance of the academic, organisational and practice contexts through which students learn (Table 4 )[ 6 ].
Case study findings can have implications both for theory development and theory testing. They may establish, strengthen or weaken historical explanations of a case and, in certain circumstances, allow theoretical (as opposed to statistical) generalisation beyond the particular cases studied[ 12 ]. These theoretical lenses should not, however, constitute a strait-jacket and the cases should not be "forced to fit" the particular theoretical framework that is being employed.
When reporting findings, it is important to provide the reader with enough contextual information to understand the processes that were followed and how the conclusions were reached. In a collective case study, researchers may choose to present the findings from individual cases separately before amalgamating across cases. Care must be taken to ensure the anonymity of both case sites and individual participants (if agreed in advance) by allocating appropriate codes or withholding descriptors. In the example given in Table 3 , we decided against providing detailed information on the NHS sites and individual participants in order to avoid the risk of inadvertent disclosure of identities[ 5 , 25 ].
What are the potential pitfalls and how can these be avoided?
The case study approach is, as with all research, not without its limitations. When investigating the formal and informal ways undergraduate students learn about patient safety (Table 4 ), for example, we rapidly accumulated a large quantity of data. The volume of data, together with the time restrictions in place, impacted on the depth of analysis that was possible within the available resources. This highlights a more general point of the importance of avoiding the temptation to collect as much data as possible; adequate time also needs to be set aside for data analysis and interpretation of what are often highly complex datasets.
Case study research has sometimes been criticised for lacking scientific rigour and providing little basis for generalisation (i.e. producing findings that may be transferable to other settings)[ 1 ]. There are several ways to address these concerns, including: the use of theoretical sampling (i.e. drawing on a particular conceptual framework); respondent validation (i.e. participants checking emerging findings and the researcher's interpretation, and providing an opinion as to whether they feel these are accurate); and transparency throughout the research process (see Table 8 )[ 8 , 18 – 21 , 23 , 26 ]. Transparency can be achieved by describing in detail the steps involved in case selection, data collection, the reasons for the particular methods chosen, and the researcher's background and level of involvement (i.e. being explicit about how the researcher has influenced data collection and interpretation). Seeking potential, alternative explanations, and being explicit about how interpretations and conclusions were reached, help readers to judge the trustworthiness of the case study report. Stake provides a critique checklist for a case study report (Table 9 )[ 8 ].
Conclusions
The case study approach allows, amongst other things, critical events, interventions, policy developments and programme-based service reforms to be studied in detail in a real-life context. It should therefore be considered when an experimental design is either inappropriate to answer the research questions posed or impossible to undertake. Considering the frequency with which implementations of innovations are now taking place in healthcare settings and how well the case study approach lends itself to in-depth, complex health service research, we believe this approach should be more widely considered by researchers. Though inherently challenging, the research case study can, if carefully conceptualised and thoughtfully undertaken and reported, yield powerful insights into many important aspects of health and healthcare delivery.
Yin RK: Case study research, design and method. 2009, London: Sage Publications Ltd., 4
Google Scholar
Keen J, Packwood T: Qualitative research; case study evaluation. BMJ. 1995, 311: 444-446.
Article CAS PubMed PubMed Central Google Scholar
Sheikh A, Halani L, Bhopal R, Netuveli G, Partridge M, Car J, et al: Facilitating the Recruitment of Minority Ethnic People into Research: Qualitative Case Study of South Asians and Asthma. PLoS Med. 2009, 6 (10): 1-11.
Article Google Scholar
Pinnock H, Huby G, Powell A, Kielmann T, Price D, Williams S, et al: The process of planning, development and implementation of a General Practitioner with a Special Interest service in Primary Care Organisations in England and Wales: a comparative prospective case study. Report for the National Co-ordinating Centre for NHS Service Delivery and Organisation R&D (NCCSDO). 2008, [ http://www.sdo.nihr.ac.uk/files/project/99-final-report.pdf ]
Robertson A, Cresswell K, Takian A, Petrakaki D, Crowe S, Cornford T, et al: Prospective evaluation of the implementation and adoption of NHS Connecting for Health's national electronic health record in secondary care in England: interim findings. BMJ. 2010, 41: c4564-
Pearson P, Steven A, Howe A, Sheikh A, Ashcroft D, Smith P, the Patient Safety Education Study Group: Learning about patient safety: organisational context and culture in the education of healthcare professionals. J Health Serv Res Policy. 2010, 15: 4-10. 10.1258/jhsrp.2009.009052.
Article PubMed Google Scholar
van Harten WH, Casparie TF, Fisscher OA: The evaluation of the introduction of a quality management system: a process-oriented case study in a large rehabilitation hospital. Health Policy. 2002, 60 (1): 17-37. 10.1016/S0168-8510(01)00187-7.
Stake RE: The art of case study research. 1995, London: Sage Publications Ltd.
Sheikh A, Smeeth L, Ashcroft R: Randomised controlled trials in primary care: scope and application. Br J Gen Pract. 2002, 52 (482): 746-51.
PubMed PubMed Central Google Scholar
King G, Keohane R, Verba S: Designing Social Inquiry. 1996, Princeton: Princeton University Press
Doolin B: Information technology as disciplinary technology: being critical in interpretative research on information systems. Journal of Information Technology. 1998, 13: 301-311. 10.1057/jit.1998.8.
George AL, Bennett A: Case studies and theory development in the social sciences. 2005, Cambridge, MA: MIT Press
Eccles M, the Improved Clinical Effectiveness through Behavioural Research Group (ICEBeRG): Designing theoretically-informed implementation interventions. Implementation Science. 2006, 1: 1-8. 10.1186/1748-5908-1-1.
Article PubMed Central Google Scholar
Netuveli G, Hurwitz B, Levy M, Fletcher M, Barnes G, Durham SR, Sheikh A: Ethnic variations in UK asthma frequency, morbidity, and health-service use: a systematic review and meta-analysis. Lancet. 2005, 365 (9456): 312-7.
Sheikh A, Panesar SS, Lasserson T, Netuveli G: Recruitment of ethnic minorities to asthma studies. Thorax. 2004, 59 (7): 634-
CAS PubMed PubMed Central Google Scholar
Hellström I, Nolan M, Lundh U: 'We do things together': A case study of 'couplehood' in dementia. Dementia. 2005, 4: 7-22. 10.1177/1471301205049188.
Som CV: Nothing seems to have changed, nothing seems to be changing and perhaps nothing will change in the NHS: doctors' response to clinical governance. International Journal of Public Sector Management. 2005, 18: 463-477. 10.1108/09513550510608903.
Lincoln Y, Guba E: Naturalistic inquiry. 1985, Newbury Park: Sage Publications
Barbour RS: Checklists for improving rigour in qualitative research: a case of the tail wagging the dog?. BMJ. 2001, 322: 1115-1117. 10.1136/bmj.322.7294.1115.
Mays N, Pope C: Qualitative research in health care: Assessing quality in qualitative research. BMJ. 2000, 320: 50-52. 10.1136/bmj.320.7226.50.
Mason J: Qualitative researching. 2002, London: Sage
Brazier A, Cooke K, Moravan V: Using Mixed Methods for Evaluating an Integrative Approach to Cancer Care: A Case Study. Integr Cancer Ther. 2008, 7: 5-17. 10.1177/1534735407313395.
Miles MB, Huberman M: Qualitative data analysis: an expanded sourcebook. 1994, CA: Sage Publications Inc., 2
Pope C, Ziebland S, Mays N: Analysing qualitative data. Qualitative research in health care. BMJ. 2000, 320: 114-116. 10.1136/bmj.320.7227.114.
Cresswell KM, Worth A, Sheikh A: Actor-Network Theory and its role in understanding the implementation of information technology developments in healthcare. BMC Med Inform Decis Mak. 2010, 10 (1): 67-10.1186/1472-6947-10-67.
Article PubMed PubMed Central Google Scholar
Malterud K: Qualitative research: standards, challenges, and guidelines. Lancet. 2001, 358: 483-488. 10.1016/S0140-6736(01)05627-6.
Article CAS PubMed Google Scholar
Yin R: Case study research: design and methods. 1994, Thousand Oaks, CA: Sage Publishing, 2
Yin R: Enhancing the quality of case studies in health services research. Health Serv Res. 1999, 34: 1209-1224.
Green J, Thorogood N: Qualitative methods for health research. 2009, Los Angeles: Sage, 2
Howcroft D, Trauth E: Handbook of Critical Information Systems Research, Theory and Application. 2005, Cheltenham, UK: Northampton, MA, USA: Edward Elgar
Book Google Scholar
Blakie N: Approaches to Social Enquiry. 1993, Cambridge: Polity Press
Doolin B: Power and resistance in the implementation of a medical management information system. Info Systems J. 2004, 14: 343-362. 10.1111/j.1365-2575.2004.00176.x.
Bloomfield BP, Best A: Management consultants: systems development, power and the translation of problems. Sociological Review. 1992, 40: 533-560.
Shanks G, Parr A: Positivist, single case study research in information systems: A critical analysis. Proceedings of the European Conference on Information Systems. 2003, Naples
Pre-publication history
The pre-publication history for this paper can be accessed here: http://www.biomedcentral.com/1471-2288/11/100/prepub
Download references
Acknowledgements
We are grateful to the participants and colleagues who contributed to the individual case studies that we have drawn on. This work received no direct funding, but it has been informed by projects funded by Asthma UK, the NHS Service Delivery Organisation, NHS Connecting for Health Evaluation Programme, and Patient Safety Research Portfolio. We would also like to thank the expert reviewers for their insightful and constructive feedback. Our thanks are also due to Dr. Allison Worth who commented on an earlier draft of this manuscript.
Author information
Authors and affiliations.
Division of Primary Care, The University of Nottingham, Nottingham, UK
Sarah Crowe & Anthony Avery
Centre for Population Health Sciences, The University of Edinburgh, Edinburgh, UK
Kathrin Cresswell, Ann Robertson & Aziz Sheikh
School of Health in Social Science, The University of Edinburgh, Edinburgh, UK
You can also search for this author in PubMed Google Scholar
Corresponding author
Correspondence to Sarah Crowe .
Additional information
Competing interests.
The authors declare that they have no competing interests.
Authors' contributions
AS conceived this article. SC, KC and AR wrote this paper with GH, AA and AS all commenting on various drafts. SC and AS are guarantors.
Rights and permissions
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Reprints and Permissions
About this article
Cite this article.
Crowe, S., Cresswell, K., Robertson, A. et al. The case study approach. BMC Med Res Methodol 11 , 100 (2011). https://doi.org/10.1186/1471-2288-11-100
Download citation
Received : 29 November 2010
Accepted : 27 June 2011
Published : 27 June 2011
DOI : https://doi.org/10.1186/1471-2288-11-100
Share this article
Anyone you share the following link with will be able to read this content:
Sorry, a shareable link is not currently available for this article.
Provided by the Springer Nature SharedIt content-sharing initiative
- Case Study Approach
- Electronic Health Record System
- Case Study Design
- Case Study Site
- Case Study Report
BMC Medical Research Methodology
ISSN: 1471-2288
- Submission enquiries: [email protected]
- General enquiries: [email protected]
Log in using your username and password
- Search More Search for this keyword Advanced search
- Latest content
- Current issue
- Write for Us
- BMJ Journals
You are here
- Volume 21, Issue 1
- What is a case study?
- Article Text
- Article info
- Citation Tools
- Rapid Responses
- Article metrics
- Roberta Heale 1 ,
- Alison Twycross 2
- 1 School of Nursing , Laurentian University , Sudbury , Ontario , Canada
- 2 School of Health and Social Care , London South Bank University , London , UK
- Correspondence to Dr Roberta Heale, School of Nursing, Laurentian University, Sudbury, ON P3E2C6, Canada; rheale{at}laurentian.ca
http://dx.doi.org/10.1136/eb-2017-102845
Statistics from Altmetric.com
Request permissions.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
What is it?
Case study is a research methodology, typically seen in social and life sciences. There is no one definition of case study research. 1 However, very simply… ‘a case study can be defined as an intensive study about a person, a group of people or a unit, which is aimed to generalize over several units’. 1 A case study has also been described as an intensive, systematic investigation of a single individual, group, community or some other unit in which the researcher examines in-depth data relating to several variables. 2
Often there are several similar cases to consider such as educational or social service programmes that are delivered from a number of locations. Although similar, they are complex and have unique features. In these circumstances, the evaluation of several, similar cases will provide a better answer to a research question than if only one case is examined, hence the multiple-case study. Stake asserts that the cases are grouped and viewed as one entity, called the quintain . 6 ‘We study what is similar and different about the cases to understand the quintain better’. 6
The steps when using case study methodology are the same as for other types of research. 6 The first step is defining the single case or identifying a group of similar cases that can then be incorporated into a multiple-case study. A search to determine what is known about the case(s) is typically conducted. This may include a review of the literature, grey literature, media, reports and more, which serves to establish a basic understanding of the cases and informs the development of research questions. Data in case studies are often, but not exclusively, qualitative in nature. In multiple-case studies, analysis within cases and across cases is conducted. Themes arise from the analyses and assertions about the cases as a whole, or the quintain, emerge. 6
Benefits and limitations of case studies
If a researcher wants to study a specific phenomenon arising from a particular entity, then a single-case study is warranted and will allow for a in-depth understanding of the single phenomenon and, as discussed above, would involve collecting several different types of data. This is illustrated in example 1 below.
Using a multiple-case research study allows for a more in-depth understanding of the cases as a unit, through comparison of similarities and differences of the individual cases embedded within the quintain. Evidence arising from multiple-case studies is often stronger and more reliable than from single-case research. Multiple-case studies allow for more comprehensive exploration of research questions and theory development. 6
Despite the advantages of case studies, there are limitations. The sheer volume of data is difficult to organise and data analysis and integration strategies need to be carefully thought through. There is also sometimes a temptation to veer away from the research focus. 2 Reporting of findings from multiple-case research studies is also challenging at times, 1 particularly in relation to the word limits for some journal papers.
Examples of case studies
Example 1: nurses’ paediatric pain management practices.
One of the authors of this paper (AT) has used a case study approach to explore nurses’ paediatric pain management practices. This involved collecting several datasets:
Observational data to gain a picture about actual pain management practices.
Questionnaire data about nurses’ knowledge about paediatric pain management practices and how well they felt they managed pain in children.
Questionnaire data about how critical nurses perceived pain management tasks to be.
These datasets were analysed separately and then compared 7–9 and demonstrated that nurses’ level of theoretical did not impact on the quality of their pain management practices. 7 Nor did individual nurse’s perceptions of how critical a task was effect the likelihood of them carrying out this task in practice. 8 There was also a difference in self-reported and observed practices 9 ; actual (observed) practices did not confirm to best practice guidelines, whereas self-reported practices tended to.
Example 2: quality of care for complex patients at Nurse Practitioner-Led Clinics (NPLCs)
The other author of this paper (RH) has conducted a multiple-case study to determine the quality of care for patients with complex clinical presentations in NPLCs in Ontario, Canada. 10 Five NPLCs served as individual cases that, together, represented the quatrain. Three types of data were collected including:
Review of documentation related to the NPLC model (media, annual reports, research articles, grey literature and regulatory legislation).
Interviews with nurse practitioners (NPs) practising at the five NPLCs to determine their perceptions of the impact of the NPLC model on the quality of care provided to patients with multimorbidity.
Chart audits conducted at the five NPLCs to determine the extent to which evidence-based guidelines were followed for patients with diabetes and at least one other chronic condition.
The three sources of data collected from the five NPLCs were analysed and themes arose related to the quality of care for complex patients at NPLCs. The multiple-case study confirmed that nurse practitioners are the primary care providers at the NPLCs, and this positively impacts the quality of care for patients with multimorbidity. Healthcare policy, such as lack of an increase in salary for NPs for 10 years, has resulted in issues in recruitment and retention of NPs at NPLCs. This, along with insufficient resources in the communities where NPLCs are located and high patient vulnerability at NPLCs, have a negative impact on the quality of care. 10
These examples illustrate how collecting data about a single case or multiple cases helps us to better understand the phenomenon in question. Case study methodology serves to provide a framework for evaluation and analysis of complex issues. It shines a light on the holistic nature of nursing practice and offers a perspective that informs improved patient care.
- Gustafsson J
- Calanzaro M
- Sandelowski M
Competing interests None declared.
Provenance and peer review Commissioned; internally peer reviewed.
Read the full text or download the PDF:
Have a language expert improve your writing
Run a free plagiarism check in 10 minutes, generate accurate citations for free.
- Knowledge Base
- Methodology
- What Is a Case Study? | Definition, Examples & Methods
What Is a Case Study? | Definition, Examples & Methods
Published on May 8, 2019 by Shona McCombes . Revised on January 30, 2023.
A case study is a detailed study of a specific subject, such as a person, group, place, event, organization, or phenomenon. Case studies are commonly used in social, educational, clinical, and business research.
A case study research design usually involves qualitative methods , but quantitative methods are sometimes also used. Case studies are good for describing , comparing, evaluating and understanding different aspects of a research problem .
Table of contents
When to do a case study, step 1: select a case, step 2: build a theoretical framework, step 3: collect your data, step 4: describe and analyze the case.
A case study is an appropriate research design when you want to gain concrete, contextual, in-depth knowledge about a specific real-world subject. It allows you to explore the key characteristics, meanings, and implications of the case.
Case studies are often a good choice in a thesis or dissertation . They keep your project focused and manageable when you don’t have the time or resources to do large-scale research.
You might use just one complex case study where you explore a single subject in depth, or conduct multiple case studies to compare and illuminate different aspects of your research problem.
Once you have developed your problem statement and research questions , you should be ready to choose the specific case that you want to focus on. A good case study should have the potential to:
- Provide new or unexpected insights into the subject
- Challenge or complicate existing assumptions and theories
- Propose practical courses of action to resolve a problem
- Open up new directions for future research
Unlike quantitative or experimental research , a strong case study does not require a random or representative sample. In fact, case studies often deliberately focus on unusual, neglected, or outlying cases which may shed new light on the research problem.
However, you can also choose a more common or representative case to exemplify a particular category, experience or phenomenon.
Here's why students love Scribbr's proofreading services
Discover proofreading & editing
While case studies focus more on concrete details than general theories, they should usually have some connection with theory in the field. This way the case study is not just an isolated description, but is integrated into existing knowledge about the topic. It might aim to:
- Exemplify a theory by showing how it explains the case under investigation
- Expand on a theory by uncovering new concepts and ideas that need to be incorporated
- Challenge a theory by exploring an outlier case that doesn’t fit with established assumptions
To ensure that your analysis of the case has a solid academic grounding, you should conduct a literature review of sources related to the topic and develop a theoretical framework . This means identifying key concepts and theories to guide your analysis and interpretation.
There are many different research methods you can use to collect data on your subject. Case studies tend to focus on qualitative data using methods such as interviews , observations , and analysis of primary and secondary sources (e.g., newspaper articles, photographs, official records). Sometimes a case study will also collect quantitative data.
The aim is to gain as thorough an understanding as possible of the case and its context.
In writing up the case study, you need to bring together all the relevant aspects to give as complete a picture as possible of the subject.
How you report your findings depends on the type of research you are doing. Some case studies are structured like a standard scientific paper or thesis , with separate sections or chapters for the methods , results and discussion .
Others are written in a more narrative style, aiming to explore the case from various angles and analyze its meanings and implications (for example, by using textual analysis or discourse analysis ).
In all cases, though, make sure to give contextual details about the case, connect it back to the literature and theory, and discuss how it fits into wider patterns or debates.
Cite this Scribbr article
If you want to cite this source, you can copy and paste the citation or click the “Cite this Scribbr article” button to automatically add the citation to our free Citation Generator.
McCombes, S. (2023, January 30). What Is a Case Study? | Definition, Examples & Methods. Scribbr. Retrieved March 15, 2023, from https://www.scribbr.com/methodology/case-study/
Is this article helpful?
Shona McCombes
Other students also liked, primary vs. secondary sources | difference & examples, what is a theoretical framework | guide to organizing, what is action research | definition & examples, what is your plagiarism score.
Try Our FREE Content Analysis Software and Find Out Where You Stand Against the Competition
When and How to Use a Case Study for Research
May 17, 2021 (Updated: February 9, 2023)
Quick Navigation
What Is Case Study Research?
Types of case studies, when should you use a case study, case study benefits, case study limitations, how to write a case study.
Imagine your company receives a string of negative reviews online. You notice a few common themes among the complaints, but you still aren’t quite sure what went wrong. Or suppose an old blog post suddenly went viral, and you’d like to know why and how to do it again. In both of these situations, a case study could be the best way to find answers.
A case study is a process whereby researchers examine a specific subject in a thorough, detailed way. The subject of a case study could be an individual, a group, a community, a business, an organization, an event, or a phenomenon. Regardless of the type of subject, case studies are in-depth investigations designed to identify patterns and cause-and-effect relationships. Case studies are often used by researchers in the field of psychology , medicine, business, social work, anthropology, education, or political science.
Because they are singular in their focus and often rely on qualitative data, case studies tend to be highly subjective. The results of a single case study cannot always be generalized and applied to the larger population. However, case studies can be valuable tools for developing a thesis or illustrating a principle. They can help researchers understand, describe, compare, and evaluate different aspects of an issue or question.
Image via Flickr by plings
Case studies can be classified according to their purpose or their subject. For instance, a case study can focus on any of the following:
- A person: Some case studies focus on one particular person. Often, the subject will be an individual with some rare characteristic or experience.
- A group: Group case studies could look at a family, a group of coworkers, or a friend group. It could be people thrown together by circumstance or who share some bond or relationship. A group case study could even focus on an entire community of people.
- An organization: An organizational case study could focus on a business, a nonprofit, an institution, or any other formal entity. The study could look at the people in the organization, the processes they use, or an incident at the organization.
- A location: An event case study focuses on a specific area. It could be used to study environmental and population changes or to examine how people use the location.
- An event: Event case studies can be used to cover anything from a natural disaster to a political scandal. Often, these case studies are conducted retrospectively, as an investigation into a past event.
In addition to different types of subjects, case studies often have different designs or purposes. Here are a few of the most common types of case studies:
- Explanatory: An explanatory case study tries to explain the why or how behind something. This type of case study works well when studying an event or phenomenon, like an airplane crash or unexpected power outage.
- Descriptive: A descriptive, or illustrative, case study is designed to shed light on an unfamiliar subject. Case studies like this provide in-depth, real-world examples of whatever the researcher wants to help the audience understand. For instance, a descriptive case study could focus on the experience of a mother with postpartum depression or on a young adult who has aged out of the foster care system.
- Exploratory: An exploratory case study, or pilot case study, often serves as the first step in a larger research project. Researchers may use a case study to help them narrow their focus, draft a specific research question, and guide the parameters of a formal, large-scale study.
- Intrinsic: An intrinsic case study has no goal beyond a deeper understanding of its subject. In this type of study, researchers are not trying to make generalized conclusions, challenge existing assumptions, or make any compare-and-contrast connections. The most interesting thing about the study is the subject itself.
- Critical Instance: A critical instance case study is similar to an explanatory or intrinsic study. Like an intrinsic study, it may have no predetermined purpose beyond investigating the subject. Like an explanatory study, it may be used to explain a cause-and-effect relationship. A critical instance case study may also be used to call into question a commonly held assumption or popular theory.
- Instrumental: An instrumental case study is the opposite of an intrinsic study because it serves a purpose beyond understanding the immediate subject. In this type of study, researchers explore a larger question through an individual case or cases. For instance, researchers could use a handful of case studies to investigate the relationship between social media use and happiness.
- Cumulative: A cumulative, or collective, case study uses information from several past studies as the basis for a new study. Because it takes into account multiple case studies, a cumulative study allows for greater generalization than a single case study. It can also be a more time- and cost-effective option since it makes use of existing research.
Case studies are often used in the exploratory phase of research to gather qualitative data. They can also be used to create, support, or refute a hypothesis and guide future research. For instance, a marketing professional might conduct a case study to discover why a viral ad campaign was so successful . They can then take any lessons they glean from the case study and apply them to future marketing efforts. A psychologist could use a case study to form a theory about the best way to treat a specific disorder. That theory could then be tested later through a large-scale controlled study.
Case studies are a good way to explore a real-world topic in-depth, illustrate a point, discuss the implications or meaning of an event, or compare the experiences of different individuals. A trainer may use a case study to bring to life what would otherwise be an abstract series of recommended action steps or to spark a conversation about how to respond in a specific scenario. Similarly, professors can use case studies to highlight key concepts from a lecture and pose questions to test students’ understanding of the material.
In some situations, case studies are the only way to compile quantitative data in an ethical manner. For instance, many of the recommendations that doctors make regarding what is or is not safe during pregnancy are based on case studies. It wouldn’t be ethical to conduct a controlled study that exposes pregnant women to potentially harmful substances, so doctors rely on the anecdotal evidence provided by case studies to find correlations and draw their conclusions.
Case studies can also be used to gather data that would be otherwise impossible or impractical to obtain. Students often use case studies for their thesis or dissertation when they lack the time or resources to conduct large-scale research. Zoologists might use existing case studies to determine the success rate of reintroducing rehabilitated animals into the wild. A historian could use case studies to explore the strategies used by dictators to gain and maintain power.
Image via Flickr by calebmmartin
Case studies can be used on their own or as a complement to other research methods, depending on the situation. The examples above are just a few instances where case studies can be useful. Case studies also work well for the following:
Providing Insight Through Qualitative Data
Case studies generally provide more qualitative data as opposed to quantitative data , and that makes them an invaluable tool for gathering insight into complex topics. Psychologists, for instance, use case studies to better understand human behavior. Crafting theories on the motives behind human actions would be difficult with quantitative data alone. The information gleaned through case studies may be subjective, but so is much of what makes us human. As individuals, we each have a unique blend of emotions, attitudes, opinions, motivations, and behaviors. Objective quantitative data is rarely the best way to identify and explain these nuances.
By their very nature, case studies allow more more intensive, in-depth study than other research methods. Rather than aiming for a large sample size, case studies follow a single subject. Often case studies are conducted over a longer period of time, and the narrow focus allows researchers to gather more detail than would be possible in a study of thousands of people. The information gleaned may not be representative of the broader population, but it does provide richer insight into the subject than other research methods.
Identifying Avenues for Future Research
Case studies are often used as the first step in a larger research project. The results of a case study cannot necessarily be generalized, but they can help researchers narrow their focus. For instance, researchers in the medical field might conduct a case study on a patient who survived an injury that typically proves fatal.
Over the course of the study, researchers may identify two or three ways in which this patient’s situation differed from others they have seen. Perhaps they identify something unique in the patient’s DNA or lifestyle choices or in the steps doctors took to treat the injury. Letting that information guide them, researchers could use other methods to deepen their understanding of those factors and perhaps develop new treatments or preventative recommendations.
Case studies can also be used in the fields of social work, politics, and anthropology to draw attention to a widespread problem and spur more research. A detailed narrative about one person’s experience will inspire more compassion than an academic paper filled with quantitative data. Stories often have a greater impact than statistics.
Challenging, Testing, or Developing Theories
Case studies can be particularly useful in the process of forming and testing theories. A case study may lead researchers to form a new theory or call into a question an existing one. They are an invaluable tool for identifying exceptions to a rule or disproving conventional wisdom.
For instance, a medical professional may write a case study about a patient who exhibited atypical symptoms to assert that the list of symptoms for a condition should be expanded. A psychologist could use a case study to determine whether the new treatment they devised for depression is effective, or to demonstrate that existing treatment methods are flawed. As the result of a case study, a marketing professional could suggest that consumers values have changed and that marketing best practices should be updated accordingly.
Enabling the Study of Unique Subjects
Some subjects would be impossible, impractical, or unethical to study through other research methods. This is true in the case of extremely rare phenomenon, many aspects of human behavior, and even some medical conditions.
Suppose a medical professional would like to gather more information about multiple-birth pregnancies with four or more fetuses. More information would be helpful because we have less information about them, but the reason we have less information is because they are so rare. Conducting case studies of a few women who are currently pregnant with multiples or have given birth to multiples in the past may be the only practical way to research them.
Case studies can also be used to gain insight into historical events and natural phenomenon — things we are not able to repeat at will. Case studies have also been used to study subjects such as a feral child , child prodigies, rare psychological conditions, crisis response, and more.
Helping People Better Understand Nuanced Concepts
Educators incorporate case studies into their lectures for a reason. Walking students through a detailed case study can make the abstract seem more real and draw out the nuances of a concept. Case studies can facilitate engaging discussions, spark thoughtful questions, and give students a chance to apply what they have learned to real-world situations.
Outside the classroom, case studies can be used to illustrate complex ideas. For instance, a well-constructed case study can highlight the unintended consequences of a new piece of legislation or demonstrate that depression does not always manifest in an obvious way. Case studies can help readers and listeners understand and care about an issue that does not directly affect them.
Despite their benefits, case studies do come with a few limitations. Compared to other research methods, case studies are often at a disadvantage in terms of the following:
Replicability
In most cases, scientists strive to create experiments that can be repeated by others. That way, other scientists can perform their own research and compare their results to those of the initial study. Assuming these other scientists achieve similar results, the replicability of the experiment lends credibility to the findings and theories of the original researchers.
One limitation of case studies is that they are often difficult, if not impossible, to replicate. Although this fact does not diminish the value of case studies, it does demonstrate that case studies are not a good fit for every research problem — at least, not on their own. Additional research would have to be performed to corroborate the results and prove or disprove any generalized theories generated by a case study.
Generalization
Generalization is another area in which case studies cannot match other research methods. A case study can help us challenge existing theories and form new ones, but its results cannot necessarily be generalized. The data we gather from a case study is only valid for that specific subject, and we cannot assume that our conclusions apply to the broader population.
Researchers or readers can attempt to apply the principles from a particular case to similar situations or incorporate the results into a more comprehensive theory. However, a case study by itself can only prove the existence of certain possibilities and exceptions, not a general rule.
Reliability
The reliability of case studies may be called into question for two reasons. The first objection centers on the fallibility of human memory and the question of whether subjects are being honest. Many case studies rely on subjects to self-report biographical details, their state of mind, their thoughts and feelings, or their behaviors.
The second issue is the Hawthorne effect, which refers to the tendency of individuals to modify their behavior when they know they are being observed. This effect makes it nearly impossible for researchers to ensure that the observations and conclusions of their case study are reliable.
Researcher Bias
Researcher bias is another potential issue with case studies. The results of a case study are by nature subjective and qualitative rather than objective and qualitative, and any findings rely heavily on the observations and narrative provided by the researcher. Even the best researchers are still human, and no matter how hard they try to remain objective, they will not be able to keep their findings completely free of bias.
Researchers may have biases they are not even aware of. A researcher may over-identify with the subject and lose the benefit of a dispassionate outside perspective. If the researcher already has an opinion on the subject, they may subconsciously overlook or discount facts that contradict their pre-existing assumptions. Researcher bias can affect what the researcher observes and records, as well as how they interpret and apply their observations.
Case studies can be time-consuming and expensive to conduct. Crafting a thorough case study can be a lengthy project due to the intensive, detailed nature of this type of research. Plus, once the information has been gathered, it must be interpreted. Between the observation and analysis, a case study could take months or even years to complete. Researchers will need to be heavily involved in every step of the process, putting in a lot of time, energy, focus, and effort to ensure that the case study is as informative as possible.
Now that you understand the benefits, limitations, and types of case studies, you can follow these steps to write your own:
- Determine your objective. Write out your research problem, question, or goal. If you aren’t sure, ask yourself questions like, “What am I trying to accomplish? What do I need to know? What will success look like?” Be clear and specific. Your answers will help you choose the right type of case study for your needs.
- Review the research. Before delving into your case study, take some time to review the research that is already available. The information you gather during this preliminary research can help guide your efforts.
- Choose a subject. Decide what or who the subject of your case study will be. For instance, if you are conducting a case study to find out how businesses have been affected by new CDC guidelines, you will need to choose a specific restaurant or retailer. In some cases, you may need to draft a release form for the subject to sign so that you will be able to publish your study.
- Gather information. Case studies about a person, organization, or group may rely on questionnaires or interviews to gather information. If you are studying an event, you might use a combination of academic research and witness interviews. In some cases, you will record your own observations as part of the study.
- Write a report. Most case studies culminate in a written report, similar to a research paper. Most case studies include five sections : an introduction, a literature review, an explanation of your methods, a discussion of your findings and the implications, followed by a conclusion.
- Publish your findings. Once you’ve written your case study, consider the most engaging way to present your findings. A well-written research article is a good place to start, but going a step further will maximize the impact of your research. For instance, you could design an infographic to highlight key findings or commission an animated video to turn your case study into a visual narrative.
Whether research is your primary occupation or only an incidental part of your job, you can benefit from a solid understanding of what case studies are, how they work, and when to use them. Use the information and steps above to design and write a case study that will provide the answers you’re looking for.
“From creating content in various languages to helping with idea creation, the CopyPress team has been a pleasure to work with.”
Mattias Bergehed
Head of SEO at LeoVegas
“Thoroughly impressed with the quality and speed!”
Kimberly Hale
Project Manager at CareerBuilder
“It's infinitely cheaper and easier for me to use CopyPress rather than in-house, they handle it all for me. It's easy for us to scale up quickly, because they've got a stable of writers that know exactly how to write exactly what we're looking for.”
Greg Gifford
VP of Search at SearchLab
Microsoft Excel makes it easy to record, track, and work with your business’s financial data, like the benefits from...
Just because an image is available to view, copy, or save on the internet doesn’t mean it’s free or...
In our digital age, it’s important to know the best ways to reach your target audience and boost your...
RECENT ARTICLES
“CopyPress has been a wonderful partner for us; the team is involved in our entire content marketing process from helping to determine which blog topics to write, writing them, and ensuring they get seen by our desired audience. Working with CopyPress has been great and I would recommend them to anyone!”
Joe Sinkwitz
CEO and Founder at Intellifluence
Read More About Measurement
23 Feb 2023
15 Feb 2023
The Main Purpose of Case Studies and How to Effectively Hit the Target
Case studies generally have the following structure: it starts with a problem, then, outlines the various different potential solutions available. This is, then, followed by proven cases where one of the solutions discussed resulted in a company, organization or individual solving the problem outlined. The main purpose of case studies, therefore, is to find a real-life application of a theoretical concept or solution. Most of the time, problems are or can be solved theoretically.
The actual implementation of the solution, however, can often be an unpredictable event. The world today is very volatile, and what is true today might not necessarily be true the next day. For any solution to be trusted, it is important to prove that it can be translated from the books or classroom to the field and that it can, then, work effectively when this happens.
How to Effectively Hit the Target
However, for the case study to be truly useful, one must select the right case for study. The first step when choosing a case is to consider the purpose. When determining the purpose, think about the learning points you might wish to illustrate in the case, the people who will read the case study, and how it will eventually be presented to them. The best case study will be one that will allow you to demonstrate the usefulness of the concept being passed across. Further, even with the right content, the tone, language, and style of the case study determine how well it is taken in. When writing or presenting the case study, approach it from a straightforward expression style, one that will emphasize on the most part of the case with respect to the idea being put forth.
In the modern dynamic and current world, the most useful information will be the one which is up to date. For instance, in a business environment where one needs to forecast the demand for products they are developing, they will require up to date information on consumer preferences to help them make the right decisions. As a student writing a case study, one of the most important factors to consider when choosing a case for the study is its currency. This does not mean, however, that old case studies are useless. The key is to know when the current case is appropriate, and when it might be useful to incorporate concepts from an old case.
Most of the time, case study research involves one specific concept. Therefore, the complexity of the case chosen will determine how and whether the idea is passed across effectively. In situations where an appropriate case might be too complex, then, one might benefit from subdividing the case study into several different sections and choosing the most appropriate one.
As a student, the case study is one of the more effective research techniques. We hope that with these tips, choosing and writing case studies will definitely be much easier.
Order a custom written paper from professional writer
Reasons to choose us, flexibility, full control over orders, self-motivated writers, confidentiality and security.
- Jane Copland
- Lily Wilson
- Steven Arndt
- Abstract Samples
- Advice for Writers
- Article Examples
- Book Review
- Case Study Examples
- College Life
- Discussion Topics
- Eminent Personalities in Literature
- Essay Contest
- Essay Examples
- Interesting Stories
- International Education
- Paper Topics
- Presentation Examples
- Project Examples
- Report Samples
- Research Paper Examples
- Speech Examples
- Thesis Samples
- Useful Tips
- Writing News
- Writing Tips and How-to's
- Essay Writing Service
- Term Paper Writing Service
- Research Paper Writing Service
- Thesis Paper Writing Service
- Dissertation Writing Service
- Assignment Writing Service
- Report Writing Service
- Review Writing Service
- Speech Writing Service
- Presentation Writing Service
- Capstone Project Writing Service
- Case Study Writing Service
- Coursework Writing Service
- Homework Writing Service
- Creative Writing Service
- Buy Annotated Bibliography
- Admission Essay Writing Service
- Scholarship Essay Writing Service
Our statistics
IMAGES
VIDEO
COMMENTS
A case study is a research approach that is used to generate an in-depth, multi-faceted understanding of a complex issue in its real-life context. It is an
The purpose of a case study is to learn as much as possible about an individual or group so that the information can be generalized to many
Case studies capture a range of perspectives, as opposed to the single view of an individual you get with a survey response or interview. This
A case study is a research approach that is used to generate an in-depth, multi-faceted understanding of a complex issue in its real-life
Case study methodology serves to provide a framework for evaluation and analysis of complex issues. It shines a light on the holistic nature of nursing practice
A case study is an appropriate research design when you want to gain concrete, contextual, in-depth knowledge about a specific real-world
The general purpose of a case study is to: ... As with reports (see Writing), there are two major kinds of case studies: problem-solving case studies and
Case studies are often used in the exploratory phase of research to gather qualitative data. They can also be used to create, support, or refute
The goal of case study research is to understand the complexity of a case in the most complete way possible. For this reason, case study research often involves
The main purpose of case studies, therefore, is to find a real-life application of a theoretical concept or solution. Most of the time