Methods of Research – Case Study

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.

Case studies usually involve the detailed study of a particular case (a person or small group). Various methods of data collection and analysis are used but this typically includes observation and interviews and may involve consulting other people and personal or public records. The researchers may be interested in a particular phenomenon (e.g. coping with a diagnosis or a move into residential care) and select one or more individuals in the respective situation on whom to base their case study/studies. Case studies have a very narrow focus which results in detailed descriptive data which is unique to the case(s) studied. Nevertheless, it can be useful in clinical settings and may even challenge existing theories and practices in other domains.

The case study research design is also useful for testing whether scientific theories and models actually work in the real world. You may come out with a great computer model for describing how the ecosystem of a rock pool works but it is only by trying it out on a real life pool that you can see if it is a realistic simulation.

For psychologists, anthropologists and social scientists they have been regarded as a valid method of research for many years. Scientists are sometimes guilty of becoming bogged down in the general picture and it is sometimes important to understand specific cases and ensure a more holistic approach to research.

Case studies can be produced by following a formal research method. These case studies are likely to appear in formal research venues, as journals and professional conferences, rather than popular works. The resulting body of ‘case study research’ has long had a prominent place in many disciplines and professions, ranging from psychology, anthropology, sociology, and political science to education, clinical science, social work, and administrative science.

Thomas offers the following definition of case study:

“Case studies are analyses of persons, events, decisions, periods, projects, policies, institutions, or other systems that are studied holistically by one or more method. The case that is the subject of the inquiry will be an instance of a class of phenomena that provides an analytical frame — an object — within which the study is conducted and which the case illuminates and explicates.”

According to J. Creswell, data collection in a case study occurs over a “sustained period of time.”

“A case study is both the process of learning about the case and the product of our learning” (p.237) – Stake

“The all-encompassing feature of a case study is its intense focus on a single phenomenon within its real-life context…[Case studies are] research situations where the number of variables of interest far outstrips the number of datapoints”

(Yin 1999 p. 1211, Yin 1994 p. 13)

“A case study is an empirical inquiry that

  • Investigates a contemporary phenomenon in depth and within its real-life context, especially when
  • The boundaries between phenomenon and context are not clearly evident.” (Yin 2009 p18)

(Yin 1999 p. 1211, Yin 1994 p. 13)

“Case study is a phenomenon of some sort occurring in a bounded context” (Miles and Huberman p. 25)

“In-depth study undertaken of one particular ‘case’, which could be a site, individual or policy” ( Green and Thorogood p. 284)

“Case study is an instance of a class of events [where] the term class of events refers to a phenomenon of scientific interest…that the investigator chooses to study with the aim of developing theory regarding causes of similarities or differences among instances (cases) of that class of events” (George and Bennett p. 17)”

One approach sees the case study defined as a research strategy, an empirical inquiry that investigates a phenomenon within its real-life context. Case-study research can mean single and multiple case studies, can include quantitative evidence, relies on multiple sources of evidence, and benefits from the prior development of theoretical propositions. As such, case study research should not be confused with qualitative research, as case studies can be based on any mix of quantitative and qualitative data. Similarly, single-subject research might be taken as case studies of a sort, except that the repeated trials in single-subject research permit the use of experimental designs that would not be possible in typical case studies. At the same time, the repeated trials can provide a statistical framework for making inferences from quantitative data

Case selection and structure

An average, or typical case, is often not the richest in information. In clarifying lines of history and causation it is more useful to select subjects that offer an interesting, unusual or particularly revealing set of circumstances

Three types of cases may thus be distinguished for selection:

  1. Key cases
  2. Outlier cases
  3. Local knowledge cases

Types of case studies

Don W. Stacks identifies three types of case study as used in public-relations research:

  1. Linear,
  2. Process-oriented,
  3. Grounded.

Under the more generalized category of case study exist several subdivisions, each of which is custom selected for use depending upon the goals and/or objectives of the investigator. These types of case study include the following:

  • Illustrative Case Studies. These are primarily descriptive studies. They typically utilize one or two instances of an event to show what a situation is like. Illustrative case studies serve primarily to make the unfamiliar familiar and to give readers a common language about the topic in question.
  • Exploratory (or pilot) Case Studies. These are condensed case studies performed before implementing a large scale investigation. Their basic function is to help identify questions and select types of measurement prior to the main investigation. The primary pitfall of this type of study is that initial findings may seem convincing enough to be released prematurely as conclusions.
  • Cumulative Case Studies. These serve to aggregate information from several sites collected at different times. The idea behind these studies is the collection of past studies will allow for greater generalization without additional cost or time being expended on new, possibly repetitive studies.
  • Critical Instance Case Studies. These examine one or more sites for either the purpose of examining a situation of unique interest with little to no interest in generalizability, or to call into question or challenge a highly generalized or universal assertion. This method is useful for answering cause and effect questions.

Example of epistemological approaches that may be used in case study research




Key references


Involves questioning one’s own assumptions taking into account the wider political and social environment.

It can possibly neglect other factors by focussing only on power relationships and may give the researcher a position that is too privileged.

Howcroft and Trauth, Blakie, Doolin

Interprets the limiting conditions in relation to power and control that are thought to influence behaviour.

Bloomfield and Best


Involves understanding meanings/contexts and processes as perceived from different perspectives, trying to understand individual and shared social meanings. Focus is on theory building.

Often difficult to explain unintended consequences and for neglecting surrounding historical contexts

Stake, Doolin


Involves establishing which variables one wishes to study in advance and seeing whether they fit in with the findings. Focus is often on testing and refining theory on the basis of case study findings.

It does not take into account the role of the researcher in influencing findings.

Yin, Shanks and Parr

Example of a checklist for rating a case study proposal


Clarity: Does the proposal read well?

Integrity: Do its pieces fit together?

Attractiveness: Does it pique the reader’s interest?


The case: Is the case adequately defined?

The issues: Are major research questions identified?

Data Resource: Are sufficient data sources identified?


Case Selection: Is the selection plan reasonable?

Data Gathering: Are data-gathering activities outlined?

Validation: Is the need and opportunity for triangulation indicated?


Access: Are arrangements for start-up anticipated?

Confidentiality: Is there sensitivity to the protection of people?

Cost: Are time and resource estimates reasonable?

How to Design and Conduct a Case Study

The advantage of the case study research design is that you can focus on specific and interesting cases. This may be an attempt to test a theory with a typical case or it can be a specific topic that is of interest. Research should be thorough and note taking should be meticulous and systematic.

The first foundation of the case study is the subject and relevance. In a case study, you are deliberately trying to isolate a small study group, one individual case or one particular population.

For example, statistical analysis may have shown that birthrates in African countries are increasing. A case study on one or two specific countries becomes a powerful and focused tool for determining the social and economic pressures driving this.

In the design of a case study, it is important to plan and design how you are going to address the study and make sure that all collected data is relevant. Unlike a scientific report, there is no strict set of rules so the most important part is making sure that the study is focused and concise; otherwise you will end up having to wade through a lot of irrelevant information.

It is best if you make yourself a short list of 4 or 5 bullet points that you are going to try and address during the study. If you make sure that all research refers back to these then you will not be far wrong.

With a case study, even more than a questionnaire or survey, it is important to be passive in your research. You are much more of an observer than an experimenter and you must remember that, even in a multi-subject case, each case must be treated individually and then cross case conclusions can be drawn.

How to Analyze the Results

Analyzing results for a case study tends to be more opinion based than statistical methods. The usual idea is to try and collate your data into a manageable form and construct a narrative around it.

Use examples in your narrative whilst keeping things concise and interesting. It is useful to show some numerical data but remember that you are only trying to judge trends and not analyze every last piece of data. Constantly refer back to your bullet points so that you do not lose focus.

It is always a good idea to assume that a person reading your research may not possess a lot of knowledge of the subject so try to write accordingly.

In addition, unlike a scientific study which deals with facts, a case study is based on opinion and is very much designed to provoke reasoned debate. There really is no right or wrong answer in a case study.

Potential pitfalls and mitigating actions when undertaking case study research

Potential pitfall

Mitigating action

Selecting/conceptualising the wrong case(s) resulting in lack of theoretical generalisations

Developing in-depth knowledge of theoretical and empirical literature, justifying choices made

Collecting large volumes of data that are not relevant to the case or too little to be of any value

Focus data collection in line with research questions, whilst being flexible and allowing different paths to be explored

Defining/bounding the case

Focus on related components (either by time and/or space), be clear what is outside the scope of the case

Lack of rigour

Triangulation, respondent validation, the use of theoretical sampling, transparency throughout the research process

Ethical issues

Anonymise appropriately as cases are often easily identifiable to insiders, informed consent of participants

Integration with theoretical framework

Allow for unexpected issues to emerge and do not force fit, test out preliminary explanations, be clear about epistemological positions in advance

Stake’s checklist for assessing the quality of a case study report

1. Is this report easy to read?

2. Does it fit together, each sentence contributing to the whole?

3. Does this report have a conceptual structure (i.e. themes or issues)?

4. Are its issues developed in a series and scholarly way?

5. Is the case adequately defined?

6. Is there a sense of story to the presentation?

7. Is the reader provided some vicarious experience?

8. Have quotations been used effectively?

9. Are headings, figures, artefacts, appendices, indexes effectively used?

10. Was it edited well, then again with a last minute polish?

11. Has the writer made sound assertions, neither over- or under-interpreting?

12. Has adequate attention been paid to various contexts?

13. Were sufficient raw data presented?

14. Were data sources well chosen and in sufficient number?

15. Do observations and interpretations appear to have been triangulated?

16. Is the role and point of view of the researcher nicely apparent?

17. Is the nature of the intended audience apparent?

18. Is empathy shown for all sides?

19. Are personal intentions examined?

20. Does it appear individuals were put at risk?

Table 1

Example of a case study investigating the reasons for differences in recruitment rates of minority ethnic people in asthma research

Context: 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.

Objective: To investigate approaches to bolster recruitment of South Asians into UK asthma studies through qualitative research with US and UK researchers, and UK community leaders.

Study design: Single intrinsic case study

The case: Centred on the issue of recruitment of South Asian people with asthma.

Data collection: In-depth interviews were conducted with asthma researchers from the UK and US. A supplementary questionnaire was also provided to researchers.

Analysis: Framework approach.

Key findings: Barriers to ethnic minority recruitment were found to centre around:

   1. 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.

   2. Stereotypes and prejudices: 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.

   3. 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.

   4. Above all, however, it appeared that the overriding importance of the US National Institute of Health’s policy to mandate the inclusion of minority ethnic people (and women) had a major impact on shaping the attitudes and in turn the experiences of US researchers’; the absence of any similar mandate in the UK meant that UK-based researchers had not been forced to challenge their existing practices and they were hence unable to overcome any stereotypical/prejudicial attitudes through experiential learning.

Table 2

Example of a case study investigating the process of planning and implementing a service in Primary Care Organisations

Context: 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.

Objective: 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.

Study design: Multiple-case design of respiratory services in health regions in England and Wales.

The cases: Four PCOs.

Data collection: Face-to-face and telephone interviews, e-mail discussions, local documents, patient diaries, news items identified from local and national websites, national workshop.

Analysis: Reading, coding and comparison progressed iteratively.

Key findings:

   1. 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 2006 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.

   2. Implementing workforce reconfiguration was strongly influenced by the negotiation and contest among local clinicians and managers about “ownership” of work and income.

   3. 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.

Main limitations: It was only possible to undertake in-depth work in a selective number of PCOs and, even within these selected PCOs, it was not possible to interview all informants of potential interest and/or obtain all relevant documents. This work was conducted in the early stages of a major NHS reorganisation in England and Wales and thus, events are likely to have continued to evolve beyond the study period; we therefore cannot claim to have seen any of the stories through to their conclusion.

Table 3

Example of a case study investigating the introduction of the electronic health records[5]

Context: Healthcare systems globally are moving from paper-based record systems to electronic health record systems. In 2002, the NHS in England embarked on the most ambitious and expensive IT-based transformation in healthcare in history seeking to introduce electronic health records into all hospitals in England by 2010.

Objectives: To describe and evaluate the implementation and adoption of detailed electronic health records in secondary care in England and thereby provide formative feedback for local and national rollout of the NHS Care Records Service.

Study design: A mixed methods, longitudinal, multi-site, socio-technical collective case study.

The cases: Five NHS acute hospital and mental health Trusts that have been the focus of early implementation efforts.

Data collection: Semi-structured interviews, documentary data and field notes, observations and quantitative data.

Analysis: Qualitative data were analysed thematically using a socio-technical coding matrix, combined with additional themes that emerged from the data.

Key findings:

   1. Hospital electronic health record systems have developed and been implemented far more slowly than was originally envisioned.

   2. The top-down, government-led standardised approach needed to evolve to admit more variation and greater local choice for hospitals in order to support local service delivery.

   3. A range of adverse consequences were associated with the centrally negotiated contracts, which excluded the hospitals in question.

   4. The unrealistic, politically driven, timeline (implementation over 10 years) was found to be a major source of frustration for developers, implementers and healthcare managers and professionals alike.

Main limitations: We were unable to access details of the contracts between government departments and the Local Service Providers responsible for delivering and implementing the software systems. This, in turn, made it difficult to develop a holistic understanding of some key issues impacting on the overall slow roll-out of the NHS Care Record Service. Early adopters may also have differed in important ways from NHS hospitals that planned to join the National Programme for Information Technology and implement the NHS Care Records Service at a later point in time.

Table 4

Example of a case study investigating the formal and informal ways students learn about patient safety

Context: There is a need to reduce the disease burden associated with iatrogenic harm and considering that healthcare education represents perhaps the most sustained patient safety initiative ever undertaken, it is important to develop a better appreciation of the ways in which undergraduate and newly qualified professionals receive and make sense of the education they receive.

Objectives: To investigate the formal and informal ways pre-registration students from a range of healthcare professions (medicine, nursing, physiotherapy and pharmacy) learn about patient safety in order to become safe practitioners.

Study design: Multi-site, mixed method collective case study.

The cases: Eight case studies (two for each professional group) were carried out in educational provider sites considering different programmes, practice environments and models of teaching and learning.

Data collection and analysis: Structured in phases relevant to the three knowledge contexts:

Phase 1: Academic context

Documentary evidence (including undergraduate curricula, handbooks and module outlines), complemented with a range of views (from course leads, tutors and students) and observations in a range of academic settings.

Phase 2a: Organisational context

Policy and management views of patient safety and influences on patient safety education and practice. NHS policies included, for example, implementation of the National Patient Safety Agency’s Seven Steps to Patient Safety, which encourages organisations to develop an organisational safety culture in which staff members feel comfortable identifying dangers and reporting hazards.

Phase 2b: Practice context

The cultures to which students are exposed i.e. patient safety in relation to day-to-day working. NHS initiatives included, for example, a hand washing initiative or introduction of infection control measures.

Key findings:

   1. Practical, informal, learning opportunities were valued by students. On the whole, however, students were not exposed to nor engaged with important NHS initiatives such as risk management activities and incident reporting schemes.

   2. NHS policy appeared to have been taken seriously by course leaders. Patient safety materials were incorporated into both formal and informal curricula, albeit largely implicit rather than explicit.

   3. Resource issues and peer pressure were found to influence safe practice. Variations were also found to exist in students’ experiences and the quality of the supervision available.

Main limitations: The curriculum and organisational documents collected differed between sites, which possibly reflected gatekeeper influences at each site. The recruitment of participants for focus group discussions proved difficult, so interviews or paired discussions were used as a substitute.


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