THE CASE STUDY METHOD
Like a carpenter or a physician, personality researchers must use many dif-
ferent tools to be effective in their job. Although most personality psycholo-gists rely on empirical studies with large numbers of participants to test
their ideas, there are other ways to examine individual differences and per-
sonality processes. One procedure occa sionally used by personality research-
e r si st h e case study method , an in-depth evaluation of a single individual
(or sometimes a few individuals). Typi cally, the participant in a case study
is a psychotherapy client suffering from a problem of interest to the investi-
gator. The researcher records in great detail the person ’s history, current be-
havior, and changes in behavior over the course of the investigation, whichsometimes lasts for years. Case study data are usually descriptive. That is,rather than reporting a lot of numbers and statistical analyses, investigators
describe their impressions of what the person did and what the behavior
means. Researchers occasionally include quantitative assessments, such asrecording how many times the person washes his or her hands in a 24-hour
period. However, data comparing the individual with another group or an-
other person are rarely reported.
As you will see throughout this book, case studies have played an impor-
tant role in the history of personality psychology. Sigmund Freud relied al-
most exclusively on his own in-depth analysis of patients when formulating
ideas about personality. In fact, many of Freud ’s initial insights into the func-
tions of the human mind came from his observations of one early patient,
Anna O., whose story is told in Chapter 3. Gordon Allport, the first psychol-
ogist to promote the concept of traits, argued that we cannot capture the es-
sence of a whole personality without an in-depth analysis of a single
individual. Humanistic theorists, most notably Carl Rogers, developed their
unique concept of human nature through the extensive evaluation of psycho-
therapy clients. Behaviorists also sometimes rely on case studies to illustrate
various aspects of their theories and the effectiveness of their therapies. Forexample, we will review John B. Watson ’s work with an orphaned infant
named “Little Albert ”in Chapter 13. This famous case study has been widely
cited as evidence for the behaviorist explanation of abnormal behaviors.
Limitations of the Case Study Method
The widespread use of the case study method by prominent psychologists may
surprise you at first given some of the obvious weaknesses of this method. First
is the problem of generalizing from a single individual to other people. Justbecause one person reacts to events in a certain way does not mean all people
do. In fact, many case study participants come to the attention of personality
theorists when they seek out psychotherapy, often because they feel differentfrom others. One reason researchers randomly assign many people to condi-
tions in their studies is to eliminate the bias that comes from examining just a
few people who may or may not represent a larger population.
Second is the problem of determining cause-and-effect relationships with
the case study method. For example, a client with a fear of water may recalla traumatic experience of nearly drowning as a child. Although we can28 CHAPTER 2 Personality Research Methods