Contents

CHAPTER 9: Single-Case Designs and Small-n Research 283psychologist may have little control over extraneous variables (e.g., home andwork environments that influence the client’s symptoms). Thus, a fundamentalcharacteristic of case studies is that they often lack a high degree of control. Withoutcontrol, it is difficult for researchers to make valid inferences about variablesthat influence the individual’s behavior (including any treatment). Degree ofcontrol is one distinguishing feature between the case study method and singlesubjectexperimental designs, with single-subject experimental designs havinga higher degree of control (see, for example, Kazdin, 2002).The form and content of case studies are extremely varied. Published casestudies may be only a few printed pages long or may fill a book. Many aspectsof the case study method make it a unique means of studying behavior.It differs from more experimental approaches in terms of its goals, themethods used, and the types of information obtained (Kazdin, 2002). Forexample, the case study method is often characterized as “exploratory” innature and a source of hypotheses and ideas about behavior (Bolgar, 1965).Experimental approaches, on the other hand, are frequently viewed as opportunitiesto test specific hypotheses. The case study method has sometimesbeen viewed as antagonistic to more controlled methods of investigation. Amore appropriate perspective is suggested by Kazdin (2002), who sees thecase study method as interrelated with and complementary to other research methodsin psychology.The case study method offers both advantages and disadvantages to theresearch psychologist (see, for example, Bolgar, 1965; Hersen & Barlow, 1976;Kazdin, 2002). Before reviewing its advantages and disadvantages, however,we will illustrate the method with a summary of an actual case study reportedby Kirsch (1978). It is important that you read this slightly abbreviated versionof a case study carefully because we will review it when discussing the advantagesand disadvantages of the case study method (see Box 9.1).BOX 9.1CAN CLIENTS BE THEIR OWN THERAPISTS? A CASE STUDY ILLUSTRATIONThis article reports on the use of self-managementtraining (SMT), a therapeutic strategy which capitalizeson the advantages of brief therapies, whileat the same time reducing the danger of leavingtoo many tasks not fully accomplished. . . . Theessence of this approach involves teaching theclient how to be his or her own behavior therapist.The client is taught how to assess problems alongbehavioral dimensions and to develop specifictactics, based on existing treatment techniques,for overcoming problems. As this process occurs,the traditional client–therapist relationship isaltered considerably. The client takes on the dualrole of client and therapist, while the therapisttakes on the role of supervisor.The case of SusanSusan, a 28-year-old married woman, enteredtherapy complaining that she suffered from adeficient memory, low intelligence, and lack ofself-confidence. The presumed deficiencies“caused” her to be inhibited in a number of socialsituations. She was unable to engage in discussionsabout films, plays, books, or magazine(continued)