Chapter 8: Case study

Darshini Ayton

Learning outcomes

Upon completion of this chapter, you should be able to:

  • Identify the key terms and concepts used in qualitative case study research.
  • Discuss the advantages and disadvantages of qualitative case study research.

What is a case study?

The key concept in a case study is context.

In qualitative research, case studies provide in-depth accounts of events, relationships, experiences or processes. Stemming from the fields of evaluation, political science and law, the aim of a qualitative case study is to explore a phenomenon within the context of the case1 and to answer how and why research questions.2 The contextual conditions are relevant to the phenomenon under study and the contextual factors tend to lie with the case.1 From the outset it is important (a) to determine who or what is your case – this can be a person, program, organisation or group, or a process – and (b) to articulate the phenomenon of interest.

An example of why context is important in understanding the phenomenon of interest is a study of health promotion action by local churches in Victoria, Australia.3 The phenomenon under study was health promotion action, with 10 churches comprising the cases, which were mapped across the framework of health promotion approaches.4 The contextual factors included church denomination (Baptist, Church of Christ, Uniting, Anglican, Catholic and Salvation Army), size (small, medium and large), location (rural and metropolitan), partnerships with external organisations (government, local schools and social welfare organisations) and theological orientation (traditional, modern or postmodern), to understand the phenomenon of health promotion action. Data collection took 12 months and involved interviews with 37 church leaders, 10 focus groups with volunteers, 17 instances of participant observation of church activities, including church services, youth events, food banks and community meals, and 12 documentary analyses of church websites, newsletters and annual reports. The case studies identified and illustrated how and why three different expressions of church – traditional, new modern and emerging – led to different levels and types of health promotion activities.

Three prominent qualitative case study methodologists, Robert Stake, Robert Yin and Sharan Merriams, have articulated different approaches to case studies and their underpinning philosophical and paradigmatic assumptions. Table 8 outlines these approaches, based on work by Yazan,5 whose expanded table covers characteristics of case studies, data collection and analysis.

Table 8.1. Comparison of case study terms used by three key methodologists

Book Title The Art of Case Study Research6 Case Study Research:
Design and Methods.7
Qualitative Research and Case Study Applications in Education.8
First author and year Stake, 1995 Yin, 2002 Merriam, 1998
Definition of qualitative case study study of the particularity and complexity of a single case, coming to understand its activity within important circumstances’(pxi) empirical inquiry that investigates a contemporary phenomenon within its real-life context…relies on multiple sources of
‘an intensive, holistic description
and analysis of a bounded phenomenon such as a program, an institution, a person, a process, or a social unit’(pxiii)
Paradigm Constructivism Positivism Constructivism
Definition of a case ‘a specific, a complex, functioning thing, more specifically an integrated system’ which ‘has a boundary and working parts’ and purposive (in social sciences and human services)(p2) ‘a contemporary
phenomenon within its real life context, especially when the boundaries between a phenomenon and context are not clear and the researcher has little control over the phenomenon and context’(p13)
‘a thing, a single entity, a unit around which there are boundaries’(p27)

It can 'be a person… a program, a group…a specific policy, and so on'(p27)

Table 8.1 is derived from ‘Three Approaches to Case Study Methods in Education: Yin, Merriam, and Stake ‘  by Bedrettin Yazan, licensed under CC BY-NC-SA 4.0.5


There are several forms of qualitative case studies.1,2

Discovery-led case studies, which:

  • describe what is happening in the setting
  • explore the key issues affecting people within the setting
  • compare settings, to learn from the similarities and differences between them.

Theory-led case studies, which:

  • explain the causes of events, processes or relationships within a setting
  • illustrate how a particular theory applies to a real-life setting
  • experiment with changes in the setting to test specific factors or variables.

Single and collective case studies, where:2, 9

  • the researcher wants to understand a unique phenomenon in detail– known as an intrinsic case study
  • the researcher is seeking insight and understanding of a particular situation or phenomenon, known as an illustrative case study or instrumental case study.

In both intrinsic, instrumental and illustrative case studies, the exploration might take place within a single case. In contrast, a collective case study includes multiple individual cases, and the exploration occurs both within and between cases. Collective case studies may include comparative cases, whereby cases are sampled to provide points of comparison for either context or the phenomenon. Embedded case studies are increasingly common within multi-site, randomised controlled trials, where each of the study sites is considered a case.

Multiple forms of data collection and methods of analysis (e.g. thematic, content, framework and constant comparative analyses) can be employed, since case studies are characterised by the depth of knowledge they provide and their nuanced approaches to understanding phenomena within context.2,5 This approach enables triangulation between data sources (interviews, focus groups, participant observations), researchers and theory. Refer to Chapter 19 for information about triangulation.

Advantages and disadvantages of qualitative case studies

Advantages of using a case study approach include the ability to explore the subtleties and intricacies of complex social situations, and the use of multiple data collection methods and data from multiple sources within the case, which enables rigour through triangulation. Collective case studies enable comparison and contrasting within and across cases.

However, it can be challenging to define the boundaries of the case and to gain appropriate access to the case for the ‘deep dive’ form of analysis. Participant observation, which is a common form of data collection, can lead to observer bias. Data collection can take a long time and may require lengthy times, resources and funding to conduct the study.9

Table 8.2 provides an example of a single case study and of a collective case study.

Table 8.2. Examples of qualitative case studies

Title The lived experiences of a male survivor of intimate partner violence: a qualitative case study10 Implementing infection prevention practices across European hospitals: an in-depth qualitative assessment11
First author and year Nayback-Beebe, 2012 Clack, 2018
CC License CC BY NC 4.0
Aim ‘The purpose of this phenomenological qualitative case study… was to gain a holistic understanding of the lived-experience of a male victim of intimate partner violence and the real-life context in which the violence emerged.’(p89) ‘in-depth investigation of the main barriers, facilitators and contextual factors relevant to successfully implementing these strategies in European acute care hospitals’(p771)
Research question ‘What is the lived experience of living in and leaving an abusive intimate relationship for a white middle class male?’(p90) ‘(1) what are the main barriers and facilitators to successfully implementing CRBSI prevention procedures?; and

(2) what role do contextual factors play?’(p771)
Why a qualitative case study was conducted A single, intrinsic qualitative research study. Following Yin’s case study approach, the authors wished to uncover the contextual conditions relevant to the phenomenon under study – living in and leaving an abusive intimate relationship as a white, middle-class male. The researchers wanted to understand and explore the contextual conditions related to female-to-male perpetrated intimate partner violence. A qualitative comparative case study of 6 of the 14 hospitals participating in the Prevention of Hospital Infections by Intervention and Training (PROHIBIT) randomised controlled study on the prevention of catheter-related bloodstream infection prevention. The case study examined contextual factors that affect the implementation of an intervention, particularly across culturally, politically and economically diverse hospital settings in Europe.
Study setting and country United States of America, insights from a case study to provide nurses with an understanding that intimate partner violence occurs in the lives of men and women, and to be aware of this in the inpatient and outpatient settings. European acute-care hospitals that were participating in the PROHIBIT randomised controlled trial.
Data collection, sampling and participants Three in-depth interviews conducted for one month. The participant was a 44-year-old man who met the following inclusion criteria:

• self-reported survivor of physical, emotional, verbal abuse, harassment and/or humiliation by a current or former partner

• the violence occurred in the context of a heterosexual relationship

• was in the process of leaving or had left the relationship
Data collection before and after the implementation of an intervention and included 129 interviews (133 hours) with hospital administration, IPC and ICU leadership and staff, telephone interviews with onsite investigators alongside 41 hours of direct observations
Analysis Existential phenomenology following Colaizzi’s method for data analysis. Thematic analysis was inductive (first site visit) and deductive (second site visit), with cross-case analysis using a stacking technique; cases were grouped according to common characteristics and differences, and similarities were examined.
Key themes Theme 1. Living in the relationship – confrontation from within

Theme 2. Living in the relationship – confrontation from without

Theme 3. Leaving the relationship – realisation and relinquishment
Overarching theme: Living with a knot in your stomach
Three meta themes were identified

• implementation agendas

• resourcing

• boundary spanning


Qualitative case studies provide a study design with diverse methods to examine the contextual factors relevant to understanding the why and how of a phenomenon within a case. The design incorporates single case studies and collective cases, which can also be embedded within randomised controlled trials as a form of process evaluation.


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