Case Study Method

Key Issues, Key Texts

Roger Gomm, Martyn Hammersley, Peter Foster, Roger Gomm, Martyn Hammersley, Peter Foster

• Publisher: SAGE Publications Ltd
• Year: 2000
• ISBN:
  9781473903180
• Edition: 1
• Topic: Ciencias sociales
• Subtopic: Investigación y metodología de las ciencias sociales

This is the most comprehensive guide to the current uses and importance of case study methods in social research. The editors bring together key contributions from the field which reflect different interpretations of the purpose and capacity of case study research. The address issues such as: the problem of generalizing from study of a small number of cases; and the role of case study in developing and testing theories. The editors offer in-depth assessments of the main arguments. An annotated bibliography of the literature dealing with case study research makes this an exhaustive and indispensable guide.

CASE STUDY AND THEORY

CHAPTER 6

CASE STUDY AND THEORY IN POLITICAL SCIENCE

Harry Eckstein

[…] Case studies run the gamut from the most microscosmic to the most macrocosmic levels of political phenomena. On the micro level, we have many studies of conspicuous political personalities (political leaders such as Lincoln, Stalin, Gandhi), and of particular leadership positions and small leadership groups (the American presidency, the British Cabinet, the prime minister in British government, the operational code of the Soviet leadership, and so on). […] Beyond that level, one finds a similar profusion of case studies of transnational phenomena: specific processes of and organizations for transnational integration, particular ‘systems’ of international politics, particular crises in international relations, and the like. […]

This plenitude of case studies is not associated with any perception that they are a particularly useful means for arriving at a theoretical understanding of the subject matter of political study. […] One might explain this apparent paradox by holding that political scientists do not place a high value on theory building. No doubt this is true for many of them. But it is much less true nowadays than it used to be, and the volume, or proportion, of case studies in the field has not notably decreased.

It is in order, therefore, to raise three questions: What general role can the case study play in the development of theories concerning political phenomena? How useful is the case method at various stages of the theory-building process? And how is case study best conducted for purposes of devising theories? […]

Case studies, I will argue, are valuable at all stages of the theory-building process, but most valuable at that stage of theory building where least value is generally attached to them: the stage at which candidate theories are ‘tested’. Moreover, the argument for case studies as a means for building theories seems strongest in regard to precisely those phenomena with which the subfield of ‘comparative’ politics is most associated: macropolitical phenomena, that is, units of political study of considerable magnitude or complexity, such as nation-states and subjects virtually coterminous with them (party systems or political cultures). More precisely, the abstract brief in favour of the case study as a means of building theories seems to me to hold regardless of level of inquiry, but at the macrocosmic level practical research considerations greatly reinforce that brief. […]

Definitions

Case study and comparative study

1. The conception of case study commonly held in the social sciences is derived from, and closely similar to, that of clinical studies in medicine and psychology. Such studies are usually contrasted dichotomously (as if they were antitheses) to experimental ones, which furnish the prevalent conception of comparative study. Contrasts generally drawn between the two types of study cover virtually all aspects of inquiry: range of research; methods and techniques; manner of reporting findings; and research objectives (see Riley, 1963, pp. 32–75).

As to range of research: experimental studies are held to be conducted with large numbers of cases, constituting samples of populations, while clinical studies deal with single individuals, or at most small numbers of them not statistically representative of a populous set. Experimental studies thus are sometimes said to be ‘extensive’ and clinical ones ‘intensive’. These adjectives do not refer to numbers of individuals alone, but also involve the number of variables taken into account. In experimental studies that number is deliberately and severely limited, and pre-selected, for the purpose of discovering relationships between traits abstracted from individual wholes. Clinical study, to the contrary, tries to capture the whole individual – ‘tries to’ because it is, of course, conceded that doing so is only an approachable, not an attainable, end.

As for methods and techniques: the typical experimental study, first of all, starts with, and adheres to, a tightly constructed research design, whereas the typical clinical study is much more open-ended and flexible at all stages. The clinical researcher may have (probably must have) in mind some notions of where to begin inquiry, a sort of checklist of points to look into during its course, or perhaps even a preliminary model of the individual being studied; but actual study proceeds more by feel and improvisation than by plan. Second, the techniques most commonly associated with such inquiry in the case of ‘collective individuals’ (that is, social units) are the loose ones of participant observation (simply observing the unit from within, as if a member of it) and Verstehen (that is, empathy: understanding the meaning of actions and interactions from the members’ own points of view). The typical techniques of experimental inquiry, per contra, are those rigorous and routinized procedures of data processing and data analysis concocted to ensure high degrees of ‘non-subjective’ reliability and validity – the techniques of the statistics texts and research methods primers.

Reports of the findings of clinical study are generally characterized as narrative and descriptive: they provide case histories and detailed portraiture. Such reporting might therefore also be termed synthetic, while that of experimental studies is analytic, since it presents not depictions of ‘whole’ individuals but rather of relations among components, or elements, of them. Beyond description, clinical studies present ‘interpretation’; beyond raw data, experimental ones present rigorously evaluated ‘findings’.

It follows that the objectives of the two types of study also differ. That of experimental study is generalized knowledge: theoretical propositions. These may certainly apply to individuals but never exhaust the knowledge it is possible to have of them. Being general they necessarily miss what is particular and unique, which may or may not be a lot. The objective of clinical study, however, is precisely to capture the particular and unique, for if anything about an individual whole is such, so must be the whole per se. It is conceded that in describing an individual configuration we may get hunches about the generalizability of relations not yet experimentally studied, but only hunches, and even these only by serendipity (Merton, 1962, p. 103). Clinical study is therefore associated more with action objectives than those of pure knowledge. In the case of single individuals, it aims at diagnosis, treatment and adjustment; in that of collective individuals, at policy. This association of clinical study with adjustive action is based on the assumption that therapy and policy can hardly proceed without something approximating full knowledge of its subjects, however much general propositions may help in proceeding from clinical knowledge of a case to the appropriate manipulation of a subject. Clinical and experimental objectives draw near, asymptotically, as ‘pure’ knowledge becomes ‘applied’ (that is, in engineering models), but application is merely a possible extension of experimental knowledge while generally being an intrinsic objective of clinical research. […]

2. However, while the distinction between clinical and experimental studies is useful for contrasting the old and new comparative politics, it does not serve nearly so well in distinguishing the case study from other modes of research. At best, it can provide an initial inkling (but only an inkling) of the differences among them. […] The distinction offers a useful denotative definition of case studies in the social sciences (that is, what people usually mean by the term) but a far from useful connotative and generic one (how the term ought to be used if it is not to raise serious difficulties of meaning and classification and not to define merely one of numerous types of case study).

3. The essential objections to equating case study with clinical and comparative study with experimental inquiry all revolve on one basic point: nothing compels the clustering (hence, dichotomization) of the various characteristics used to distinguish clinical and experimental studies. Although that clustering in fact occurs very frequently in the social sciences, it does so chiefly because of dubious beliefs and assumptions. At most, the characteristics have a certain practical affinity; for example, the fewer the cases studied, the more intensive study may be, other things being equal. But no logical compulsion is at work, and the practical considerations often are not weighty.

We may certainly begin with the notion that case studies, like clinical studies, concern ‘individuals’, personal or collective (and, for tidiness of conceptualization, assume that only one individual is involved). From this, however, it does not follow that case studies must be intensive in the clinician’s sense: nothing like ‘wholistic’ study may be attempted, and the researcher may certainly aim at finding relationships between pre-selected variables – unless he assumes, a priori, that this is foolish. The research may be tightly designed and may put to use all sorts of sophisticated research techniques. (An excellent example is Osgood and Luria’s [1954] ‘blind analysis’, using the semantic differential, of a case of multiple personality.) Its results need not be cast in narrative form, and its objective can certainly be the development of general propositions rather than portraiture of the particular and unique; nor need case studies be concerned with problems of therapeutic action when they go beyond narration, depiction and subjective interpretation. […]

These points of overlap and ambivalence in the distinction between the clinical and experimental have led to a concerted attack on the dichotomy in psychology itself. One typical attack argues that the dichotomy originates in an archaic and absurd Methodenstreit between ‘mechanistic’ and ‘romantic’ views of human nature (Holt, 1962). Another argues that experimental modes of study can also be used profitably in research into single cases; this is the theme of a notable book of essays, N = 1 (Davidson and Costello, 1969). This work implies the most important definitional point of all: if case study is defined as clinical study in the traditional sense, then we not only construct a messy generic (not necessarily classificatory) concept, but also foreclose the possibility of useful argument about case study as a tool in theory building. The definition answers the question: case study and theory are at polar opposites, linked only by the fortuitous operation of serendipity.

4. This attack on the conventional idea of case study serves a constructive as well as destructive purpose. It provides ammunition for later arguments against highly restrictive views concerning the role of case study in theory building and also points the way toward a better, and simpler, definition of what case studies are.

An unambiguous definition of case study should proceed from the one sure point that has been established: case study is the study of individuals. That is about as simple as one can get – but, because of one major problem, it is too simple. The problem is that one person’s single individual may be another’s numerous cases. Take an example: in order to help break down the dichotomy between the clinical and experimental, Davidson and Costello (1969, pp. 214–32) reprint a study by Chassan on the evaluation of drug effects during psychotherapy. Chassan argues for the greater power of single-case study over the usual ‘treatment group’ versus ‘control group’ design – in this case, for determining the relative effects of tranquillizers and placebos. Readers can catch the flavour of his argument through two of his many italicized passages:

The intensive statistical study of a single case can provide more meaningful and statistically significant information than, say, only end-point observations extended over a relatively large number of patients.
The argument cited against generalization to other patients, from the result of a single case intensively studied, can actually be applied in a more realistic and devastating manner against the value of inferences … drawn from studies in which extensive rather than intensive degrees of freedom are used.

And so on, in the same vein. The whole paper is an object lesson to those who seek theoretical safety only in numbers. But there is a catch. Chassan studied only one patient, but used a large number of treatments by drug and placebo: ‘frequent observations over periods of sufficiently long duration’. The individuals here are surely not the patients, although they may be for other purposes; it is each treatment, the effects of which are being compared. It is easy enough to see the advantages of administering different treatments to the same person over a long period (hence, safety in small numbers of a sort), as against using one patient per observation (although it is to Chassan’s credit that he pointed them out in contrast to the more usual procedure). But N, despite the title of the book, in this case is not one.

If this problem arises with persons, it arises still more emphatically with ‘collective individuals’. A study of six general elections in Britain may be, but need not be, an N = 1 study. It might also be an N = 6 study. It can also be an N = 120,000,000 study. It depends on whether the subject of study is electoral systems, elections or voters.

What follows from this is that ambiguity about what constitutes an ‘individual’ (hence ‘case’) can only be dispelled by looking not at concrete entities but at the measures made of them. On this basis, a ‘case’ can be defined technically as a phenomenon for which we report and interpret only a single measure on any pertinent variable. This gets us out of answering insoluble metaphysical questions that arise because any concrete entity can be decomposed, at least potentially, into numerous entities (not excluding ‘persons’: they differ almost from moment to moment, from treatment to treatment, and consist of highly numerous cells, which consist of highly numerous particles, and so on). It also raises starkly the critical problem of this essay: What useful role can single descriptive measures (not measures of central tendency, association, correlation, variance or covariance, all of which presuppose numerous measures of each variable) play in the construction of theory? […]

Theory and theory building

We will be concerned with the utility of case studies in the development of theories in macropolitics – their utility both in themselves and, to an extent, relative to comparative (N = many) studies. While nearly everyone in the field at the present time agrees that the development of good theories is the quintessential end of political inquiry, conceptions of theory, and of the processes by which it may be developed, vary extremely in our field. This makes unavoidable a definitional exercise on theory and a review of the normal steps in theory building.

1. Two polar positions on what constitutes theory in our field can be identified. While positions range between them, they have recently been rather polarized, more often on, or very near, the extremes than between them.

On one extreme (the ‘hard’ line on theory) is the view that theory consists solely of statements like those characteristic of contemporary theoretical physics (or, better, considered to be so by influential philosophers of science). A good summary of this view, tailored to the field of political science, is presented in Holt and Richardson’s (1968) discussion of the nature of ‘paradigms’, but even better sources are the writings of scientist-philosophers such as Kemeny (1959), Popper (1959) and Hempel (1965).

Theories in this sense have four crucial traits: (1) The concepts used in them are defined very precisely, usually by stating definitions in terms of empirical referents, and are less intended to describe phenomena fully than to abstract from them characteristics useful for formulating general propositions about them. (2) The concepts are used in deductively connected sets of propositions tha...