Once you have determined what your case will be you will have

Once you have determined what your case will be, you will have to consider what your case will NOT be. One of the common pitfalls associated with case study is that there is a tendency for researchers to attempt to answer a question that is too broad or a topic that has too many objectives for one study. In order to avoid this problem, several authors including Yin (2003) and Stake (1995) have suggested that placing boundaries on a case can prevent this explosion from occurring. Suggestions on how to bind a case include: (a) by time and place (Creswell, 2003); (b) time and activity (Stake); and (c) by definition and context (Miles & Huberman, 1994). Binding the case will ensure that your 547 The Qualitative Report December 2008 study remains reasonable in scope. In the example of the study involving women who must decide whether or not to have reconstructive surgery, established boundaries would need to include a concise definition of breast cancer and reconstructive surgery. I would have to indicate where these women were receiving care or where they were making these decisions and the period of time that we wanted to learn about, for example within six months of a radical mastectomy. It would be unreasonable for me to look at all women in their 30s across Canada who had experienced breast cancer and their decisions regarding reconstructive surgery. In contrast, I might want to look at single women in their 30s who have received care in a tertiary care center in a specific hospital in South Western Ontario. The boundaries indicate what will and will not be studied in the scope of the research project. The establishment of boundaries in a qualitative case study design is similar to the development of inclusion and exclusion criteria for sample selection in a quantitative study. The difference is that these boundaries also indicate the breadth and depth of the study and not simply the sample to be included. Determining the Type of Case Study Once you have determined that the research question is best answered using a qualitative case study and the case and its boundaries have been determined, then you must consider what type of case study will be conducted. The selection of a specific type of case study design will be guided by the overall study purpose. Are you looking to describe a case, explore a case, or compare between cases? Yin (2003) and Stake (1995) use different terms to describe a variety of case studies. Yin categorizes case studies as explanatory, exploratory, or descriptive. He also differentiates between single, holistic case studies and multiple-case studies. Stake identifies case studies as intrinsic, instrumental, or collective. Definitions and published examples of these types of case studies are provided in Table 2. Table 2 Definitions and Examples of Different Types of Case Studies Case Study Type Definition Published Study Example Explanatory This type of case study would be used if you were seeking to answer a question that sought to explain the presumed causal links in real-life interventions that are too complex for the survey or experimental strategies. In evaluation language, the explanations would link program implementation with program effects (Yin, 2003). Joia (2002). Analysing a web-based e-commerce learning community: A case study in Brazil. Internet Research, 12, 305-317. Pamela Baxter and Susan Jack 548 Exploratory This type of case study is used to explore those situations in which the intervention being evaluated has no clear, single set of outcomes (Yin, 2003). Lotzkar & Bottorff (2001). An observational study of the development of a nurse-patient relationship. Clinical Nursing Research, 10, 275-294. Descriptive This type of case study is used to describe an intervention or phenomenon and the real-life context in which it occurred (Yin, 2003). Tolson, Fleming, & Schartau (2002). Coping with menstruation: Understanding the needs of women with Parkinson’s disease. Journal of Advanced Nursing, 40, 513-521. Multiple-case studies A multiple case study enables the researcher to explore differences within and between cases. The goal is to replicate findings across cases. Because comparisons will be drawn, it is imperative that the cases are chosen carefully so that the researcher can predict similar results across cases, or predict contrasting results based on a theory (Yin, 2003). Campbell & Ahrens (1998). Innovative community services for rape victims: An application of multiple case study methodology. American Journal of Community Psychology, 26, 537-571. Intrinsic Stake (1995) uses the term intrinsic and suggests that researchers who have a genuine interest in the case should use this approach when the intent is to better understand the case. It is not undertaken primarily because the case represents other cases or because it illustrates a particular trait or problem, but because in all its particularity and ordinariness, the case itself is of interest. The purpose is NOT to come to understand some abstract construct or generic phenomenon. The Hellström, Nolan, & Lundh (2005). “We do things together” A case study of “couplehood” in dementia. Dementia, 4(1), 7-22. 549 The Qualitative Report December 2008 purpose is NOT to build theory (although that is an option; Stake, 1995). Instrumental Is used to accomplish something other than understanding a particular situation. It provides insight into an issue or helps to refine a theory. The case is of secondary interest; it plays a supportive role, facilitating our understanding of something else. The case is often looked at in depth, its contexts scrutinized, its ordinary activities detailed, and because it helps the researcher pursue the external interest. The case may or may not be seen as typical of other cases (Stake, 1995). Luck, Jackson, & Usher (2007). STAMP: Components of observable behaviour that indicate potential for patient violence in emergency departments. Journal of Advanced Nursing, 59, 11-19. Collective Collective case studies are similar in nature and description to multiple case studies (Yin, 2003) Scheib (2003). Role stress in the professional life of the school music teacher: A collective case study. Journal of Research in Music Education, 51,124-136. Single or Multiple Case Study Designs Single Case In addition to identifying the “case” and the specific “type” of case study to be conducted, researchers must consider if it is prudent to conduct a single case study or if a better understanding of the phenomenon will be gained through conducting a multiple case study. If we consider the topic of breast reconstruction surgery again we can begin to discuss how to determine the “type” of case study and the necessary number of cases to study. A single holistic case might be the decision making of one woman or a single group of 30 year old women facing breast reconstruction post-mastectomy. But remember that you also have to take into consideration the context. So, are you going to look at these women in one environment because it is a unique or extreme situation? If so, you can consider a holistic single case study (Yin, 2003). Pamela Baxter and Susan Jack 550 Single Case with Embedded Units If you were interested in looking at the same issue, but now were intrigued by the different decisions made by women attending different clinics within one hospital, then a holistic case study with embedded units would enable the researcher to explore the case while considering the influence of the various clinics and associated attributes on the women’s decision making. The ability to look at sub-units that are situated within a larger case is powerful when you consider that data can be analyzed within the subunits separately (within case analysis), between the different subunits (between case analysis), or across all of the subunits (cross-case analysis). The ability to engage in such rich analysis only serves to better illuminate the case. The pitfall that novice researchers fall into is that they analyze at the individual subunit level and fail to return to the global issue that they initially set out to address (Yin, 2003). Multiple-Case Studies If a study contains more than a single case then a multiple-case study is required. This is often equated with multiple experiments. You might find yourself asking, but what is the difference between a holistic case study with embedded units and a multiple-case study? Good question! The simple answer is that the context is different for each of the cases. A multiple or collective case study will allow the researcher to analyze within each setting and across settings. While a holistic case study with embedded units only allows the researcher to understand one unique/extreme/critical case. In a multiple case study, we are examining several cases to understand the similarities and differences between the cases. Yin (2003) describes how multiple case studies can be used to either, “(a) predicts similar results (a literal replication) or (b) predicts contrasting results but for predictable reasons (a theoretical replication)” (p. 47). This type of a design has its advantages and disadvantages. Overall, the evidence created from this type of study is considered robust and reliable, but it can also be extremely time consuming and expensive to conduct. Continuing with the same example, if you wanted to study women in various health care institutions across the country, then a multiple or collective case study would be indicated. The case would still be the decision making of women in their 30s, but you would be able to analyze the different decision-making processes engaged in by women in different centers (See Case Example #3 in Table 1). Stake (1995) uses three terms to describe case studies; intrinsic, instrumental, and collective. If you are interested in a unique situation according to Stake, conduct an intrinsic case study. This simply means that you have an intrinsic interest in the subject and you are aware that the results have limited transferability. If the intent is to gain insight and understanding of a particular situation or phenomenon, then Stake would suggest that you use an instrumental case study to gain understanding. This author also uses the term collective case study when more than one case is being examined. The same example used to describe multiple case studies can be applied here. Once the case has been determined and the boundaries placed on the case it is important to consider the additional components required for designing and implementing a rigorous case study. These include: (a) propositions (which may or may not be present) (Yin, 2003, Miles & Huberman, 1994); (b) the application of a conceptual framework 551