Case Studies and Theory Development in the Social Sciences - Alexander L. George [39]
What, then, are some of the requirements that case study research must meet to overcome these difficulties?
First, the investigator should clearly identify the universe—that is, the “class” or “subclass” of events—of which a single case or a group of cases to be studied are instances. Thus, the cases in a given study must all be instances, for example, of only one phenomenon: either deterrence, coercive diplomacy, crisis management, alliance formation, war termination, the impact of domestic politics on policymaking, the importance of personality on decision-making, or whatever else the investigator wishes to study and theorize about. The identification of the class or subclass of events for any given study depends upon the problem chosen for study.
Second, a well-defined research objective and an appropriate research strategy to achieve that objective should guide the selection and analysis of a single case or several cases within the class or subclass of the phenomenon under investigation. Cases should not be chosen simply because they are “interesting” or because ample data exist for studying them.
Third, case studies should employ variables of theoretical interest for purposes of explanation. These should include variables that provide some leverage for policymakers to enable them to influence outcomes.
We turn now to a discussion of the two characteristics of the method of structured, focused comparison. From the statistical (and survey) research model, the method of structured, focused comparison borrows the device of asking a set of standardized, general questions of each case, even in single case studies. These questions must be carefully developed to reflect the research objective and theoretical focus of the inquiry. The use of a set of general questions is necessary to ensure the acquisition of comparable data in comparative studies. This procedure allows researchers to avoid the all too familiar and disappointing pitfall of traditional, in-tensive single case studies. Even when such cases were instances of a class of events, they were not performed in a comparable manner and hence did not contribute to an orderly, cumulative development of knowledge and theory about the phenomenon in question. Instead, each case study tended to go its own way, reflecting the special interests of each investigator and often being unduly shaped by whatever historical data was readily available. As a result, idiosyncratic features of each case or the specific interests of each investigator tended to shape the research questions. Not surprisingly, single case studies—lacking “scientific consciousness”—did not accumulate.
The method also requires that the study of cases be “focused”: that is, they should be undertaken with a specific research objective in mind and a theoretical focus appropriate for that objective. A single study cannot address all the interesting aspects of a historical event. It is important to recognize that a single event can be relevant for research on a variety of theoretical topics. For example, the Cuban Missile Crisis offers useful material for developing many different theories. This case may be (indeed, has been) regarded and used as an instance of deterrence, coercive diplomacy, crisis management, negotiation, domestic influence on foreign policy, personality involvement in decision-making, etc. Each of these diverse theoretical interests requires the researcher to adopt a different focus, to develop and use a different theoretical framework, and to identify a different set of data requirements. A researcher’s treatment of a historical episode must be selectively focused in accordance with the type of theory that the investigator is attempting to develop.
One reason so many case studies of a particular phenomenon in the past did not contribute much to theory development is that they lacked a clearly defined and common focus. Different investigators engaged in research on a particular