Saul McLeod , published Case studies are in-depth investigations of a single person, group, event or community. Typically, data are gathered from a variety of sources and by using several different methods e. The research may also continue for an extended period of time, so processes and developments can be studied as they happen.
The case study research method originated in clinical medicine the case history, i. The case study is not itself a research method, but researchers select methods of data collection and analysis that will generate material suitable for case studies.
Most of this information is likely to be qualitative i. The data collected can be analyzed using different theories e. All the approaches mentioned here use preconceived categories in the analysis and they are ideographic in their approach, i. Case studies are widely used in psychology and amongst the best known were the ones carried out by Sigmund Freud.
He conducted very detailed investigations into the private lives of his patients in an attempt to both understand and help them overcome their illnesses. Even today case histories are one of the main methods of investigation in abnormal psychology and psychiatry.
For students of these disciplines they can give a vivid insight into what those who suffer from mental illness often have to endure. Case studies are often conducted in clinical medicine and involve collecting and reporting descriptive information about a particular person or specific environment, such as a school. In psychology, case studies are often confined to the study of a particular individual. The information is mainly biographical and relates to events in the individual's past i.
In order to produce a fairly detailed and comprehensive profile of the person, the psychologist may use various types of accessible data, such as medical records, employer's reports, school reports or psychological test results. The interview is also an extremely effective procedure for obtaining information about an individual, and it may be used to collect comments from the person's friends, parents, employer, work mates and others who have a good knowledge of the person, as well as to obtain facts from the person him or herself.
This makes it clear that the case study is a method that should only be used by a psychologist, therapist or psychiatrist, i. There is an ethical issue of competence. 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. 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? 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 ]. 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. 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: 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. 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 ].
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.
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.
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 ]. Here, we focus on the main stages of research activity when planning and undertaking a case study; the crucial stages are: 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. 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 ]. 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. 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. 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. In another example of an intrinsic case study, Hellstrom et al. 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. Choosing a "typical" case may enable the findings to be generalised to theory i. Yin suggests two or three literal replications i. 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.
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.
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. 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.
The use of multiple sources of data data triangulation has been advocated as a way of increasing the internal validity of a study i. 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.
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. 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. Theoretical frameworks may also play an important role in integrating different sources of data and examining emerging themes. 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. The case study approach is, as with all research, not without its limitations. 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. There are several ways to address these concerns, including: 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.
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's checklist for assessing the quality of a case study report[ 8 ]. 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.
AS conceived this article. SC and AS are guarantors. We are grateful to the participants and colleagues who contributed to the individual case studies that we have drawn on.
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. National Center for Biotechnology Information , U. Published online Jun Received Nov 29; Accepted Jun This article has been cited by other articles in PMC.
Abstract The case study approach allows in-depth, multi-faceted explorations of complex issues in their real-life settings. 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.
Table 1 Example of a case study investigating the reasons for differences in recruitment rates of minority ethnic people in asthma research[ 3 ]. Minority ethnic people experience considerably greater morbidity from asthma than the White majority population.
Research has shown however that these minority ethnic populations are likely to be under-represented in research undertaken in the UK; there is comparatively less marginalisation in the US. Single intrinsic case study The case: Centred on the issue of recruitment of South Asian people with asthma. In-depth interviews were conducted with asthma researchers from the UK and US.
A supplementary questionnaire was also provided to researchers. Barriers to ethnic minority recruitment were found to centre around: The attitudes of the researchers' towards inclusion: The majority of UK researchers interviewed were generally supportive of the idea of recruiting ethnically diverse participants but expressed major concerns about the practicalities of achieving this; in contrast, the US researchers appeared much more committed to the policy of inclusion.
We found that some of the UK researchers' perceptions of ethnic minorities may have influenced their decisions on whether to approach individuals from particular ethnic groups. These stereotypes centred on issues to do with, amongst others, language barriers and lack of altruism.
Demographic, political and socioeconomic contexts of the two countries: Researchers suggested that the demographic profile of ethnic minorities, their political engagement and the different configuration of the health services in the UK and the US may have contributed to differential rates.
Open in a separate window. Table 2 Example of a case study investigating the process of planning and implementing a service in Primary Care Organisations[ 4 ]. Health work forces globally are needing to reorganise and reconfigure in order to meet the challenges posed by the increased numbers of people living with long-term conditions in an efficient and sustainable manner.
Through studying the introduction of General Practitioners with a Special Interest in respiratory disorders, this study aimed to provide insights into this important issue by focusing on community respiratory service development. To understand and compare the process of workforce change in respiratory services and the impact on patient experience specifically in relation to the role of general practitioners with special interests in a theoretically selected sample of Primary Care Organisations PCOs , in order to derive models of good practice in planning and the implementation of a broad range of workforce issues.
Multiple-case design of respiratory services in health regions in England and Wales. Face-to-face and telephone interviews, e-mail discussions, local documents, patient diaries, news items identified from local and national websites, national workshop.
Reading, coding and comparison progressed iteratively. In the screening phase of this study which involved semi-structured telephone interviews with the person responsible for driving the reconfiguration of respiratory services in 30 PCOs , the barriers of financial deficit, organisational uncertainty, disengaged clinicians and contradictory policies proved insurmountable for many PCOs to developing sustainable services.
A key rationale for PCO re-organisation in was to strengthen their commissioning function and those of clinicians through Practice-Based Commissioning. However, the turbulence, which surrounded reorganisation was found to have the opposite desired effect.
Implementing workforce reconfiguration was strongly influenced by the negotiation and contest among local clinicians and managers about "ownership" of work and income. Despite the intention to make the commissioning system more transparent, personal relationships based on common professional interests, past work history, friendships and collegiality, remained as key drivers for sustainable innovation in service development.
Case study research excels at bringing us to an understanding of a complex issue or object and can extend experience or add strength to what is already known through previous research. Case studies emphasize detailed contextual analysis of a limited number of events or conditions and their relationships.
Case study as a research method Abstract Although case study methods remain a controversial approach to data collection, they are widely recognised in many social science studies especially when in-depth explanations of a social behaviour are sought after. This article, therefore, discusses several aspects of case studies as a research.
Qualitative case study methodology provides tools for researchers to study complex phenomena within their contexts. When the approach is applied correctly, it becomes a valuable method for health science research to develop theory, evaluate programs, and develop interventions. The purpose of this paper is to guide the novice researcher in identifying the key elements for designing and. Case studies is a popular research method in business area. Case studies aim to analyze specific issues within the boundaries of a specific environment.
He presented a structured process for undertaking case study research where formal propositions or theories guide the research process and are tested as part of the outcome, highlighting his realist approach to qualitative case study research. 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.