Journal of Behavioral Medicine, Vol. 13, No. 1, 1990

Illness Cognition and Behavior: An Experimental Approach R o b e r t T. Croyle 1.3 and Peter H . Ditto 2

Accepted for publication: June 9, 1989

The study o f illness cognition and behavior has relied primarily on nonexperimental research designs. In this paper we review the results o f a program o f experimental investigations o f psychological reactions to health threats. Most o f the studies employ a new experimental paradigm developed to study illness cognition and behavior in the laboratory. The paradigm has been used in several experiments to examine the cognitive and motivational processes underlying reactions to medical test results. A converging series o f studies has shown that denial, manifested in a variety o f ways, is a common initial reaction to threatening information. In addition, the studies demonstrate that the perceived prevalence o f a health disorder is an important determinant o f its perceived seriousness. The insights gained from these studies illustrate the complementary roles o f basic experimental research and more naturalistic observational research in the formulation o f comprehensive theories o f health and illness behavior. KEY WORDS: illness cognition; illness behavior; coping; health beliefs; methodology.

INTRODUCTION Illness behavior has been defined as "any activity undertaken by an individual, who believes himself to be ill, to define the state o f his health and discover a suitable remedy" (Kasl and Cobb, 1966). We define illness cognition similarly, as any mental activity (e.g., appraisal, interpretation, recall)

1Department of Psychology,University of Utah, Salt Lake City, Utah 84112. 2Department of Psychology,Kent State University, Kent, Ohio 44242. 3To whom correspondence should be addressed. 31 0160-7715/90/0200-0031506.00/0 9 1990 Plenum Publishing Corporation

32

Croyle and Ditto

undertaken by an individual who believes himself or herself to be ill, regarding the state o f his or her health and its possible remedies. Illness cognition underlies a diverse range of phenomena studied by investigators in behavioral medicine. These include symptom appraisal, health care utilization, adjustment to illness and its treatment, and the practitioner-patient relationship. At first glance, the psychology of illness behavior would not seem to lend itself to experimental investigation. Although frequently treated as an independent variable, health status is typically an uncontrolled subject variable. But while objective health status cannot be manipulated experimentally, subjective health status can, making it possible to study illness behavior in healthy subjects. Two facts suggest this possibility. First, many health problems have no physical symptoms (e.g., essential hypertension). Many people diagnosed as having a disease or risk factor feel well. The subjective state of illness, in these cases, is initiated not by bodily sensations but by a diagnostic label. Evaluations of screening programs suggest that labeling can initiate symptoms and illness behavior even when the label is erroneous (Bloom and Monterossa, 1981; Hampton et al., 1974). Second, recent research indicates that physical symptoms are more prevalent and more ambiguous in meaning than previously assumed (Pennebaker, 1982). The interpretation of these signs depends to a large extent on cognitive and social psychological processes (Barsky and Klerman, 1983; Leventhal, 1986). Thus, many of the criteria by which individuals judge their health can be varied systematically in a laboratory setting. Illness (as opposed to disease) is a psychological rather than a biological state (Barondess, 1979); the study of illness cognition and behavior thus concentrates on any individual who feels threatened or victimized by a health disorder, regardless of his or her objective state of health. These arguments suggest that if the perception of illness can be varied experimentally, we could learn much about the thoughts and behavior of ill persons. The challenge facing the experimenter, then, is to develop a procedure for gently but convincingly inducing such perceptions in objectively healthy subjects.

T H E N E E D FOR A N E X P E R I M E N T A L P A R A D I G M

Although social psychological constructs have been applied to problems of illness cognition and behavior (Bulman and Wortman, 1977; Sanders, 1982; Taylor et al., 1984; Turnquist et al., 1988; Wills, 1987), the experimental methodology that has served as the core research technique in social psychology (Aronson et al., 1985) has not been widely utilized. The most frequently cited studies of illness cognition and behavior have used nonexperimental

Illness Cognition and Behavior

33

designs (e.g., Mechanic, 1972; Pilowsky, 1969; Zola, 1966). Even experimental social psychologists have tended to adopt nonexperimental methods in their work on health and illness (Taylor et al., 1984; Bulman and Wortman, 1977). Basic experimental research examining the ways people think about and act on illness information is an underrepresented methodological approach. Questionnaire- and interview-based surveys are both a logical and a necessary approach to the study of illness cognition and behavior. The reasons for relying on nonexperimental methods in this domain are clear. Observational approaches can examine judgments and behavior in naturalistic contexts that cannot be recreated in the experimental laboratory. Reliance on these methods does not mean, however, that an experimental approach to illness cognition and behavior is impractical. A cursory look through any social psychology textbook reveals a host of topics that initially seemed equally immune to experimental study. Topics such as human aggression, conformity, and attraction were once believed to be beyond the scope of laboratory examination. This is not to say that laboratory methods (or any other single methodology for that matter) are a sufficient research strategy in any of these domains, but rather, that laboratory research serves an important and necessary role, in a comprehensive, process-oriented research approach. This article describes an experimental paradigm that brings illness cognition and behavior into the laboratory. A summary of studies employing the paradigm suggest that it is particularly useful in understanding psychological reactions to medical diagnosis. What little is known about immediate reactions to diagnosis has been inferred largely from interviews or questionnaires administered to hospitalized patients. Traditionally, studies in this area have relied on data collected days or months after the patient became ill (e.g., Croog et ai., 1971; Taylor et al., 1984; Watson et al., 1984). Comparisons between patients and controls often provide inadequate tests of theoretical hypotheses because the critical independent variables are usually confounded. We argue that a laboratory-based experimental approach to illness cognition and behavior not only is possible, but also-when used in conjunction with nonexperimental observational methods-is a valuable tool for uncovering the specific psychological processes underlying subjective appraisals of health status and health threats. In the sections that follow, we first discuss the goals of an experimental approach to the study of illness cognition and behavior. Next we describe the paradigm and discuss how it meets these challenges and goals. We then summarize the results of several studies that have used the paradigm to explore the illness appraisal process. Finally, we discuss current areas of study where an experimental approach might be fruitfully applied and note some of the limitations of the paradigm as a research tool.

34

Croyle and Ditto

GOALS OF AN EXPERIMENTAL PARADIGM We had several goals in developing an experimental paradigm to study illness cognition and behavior. The first goal was to achieve experimental control. We wanted to study reactions to illness in a context in which we could systematically vary possible determinats of illness appraisals and observe the effects of those manipulations on specific judgments and behaviors. Such a procedure would maximize internal validity through the use of random assignment to conditions and by assuring a high level of control over extraneous variables. We also sought a paradigm that was experimentally flexible, one we could modify to model different real-world settings, and that would allow us to manipulate a wide variety of independent variables and measure many dependent variables while using a standard set of procedures. Our second goal was to maintain a reasonable level of external validity. Although laboratory experimentation invariably sacrifices some amount of resemblance to real world situations (mundane realism), another important aspect of external validity is experimental realism. As Carlsmith et al. (1976) have stated, "An experiment is realistic if the situation is realistic to the subjects-if they believe it, if they are forced to attend to it and take it seriously-in short, if it has impact on them" (p. 81). Thus, we attempted to create an experimental situation that was truly involving, one that captured the impact of the diagnostic situation it was designed to study. In part, to the extent that the paradigm is experimentally "real," we concurrently fulfill the need for mundane realism. Because of the applied nature of our research, we also have attempted to address this issue empirically by using the paradigm in settings that vary in their level of mundane realism. Finally, ethics were a paramount concern. Because the threat of illness can produce anxiety and distress, we wanted to build into our paradigm procedures to minimize the possibility of significant psychological upset. Indeed, we wanted to ensure that our subjects benefitted from their participation by learning about the psychology of health and illness.

D E S C R I P T I O N OF T H E P R O C E D U R E

Jemmott et al. (1986) were the first to use the experimental paradigm. Undergraduate students, randomly selected from the student directory, were contacted by telephone and asked to participate in a study conducted by the "Health Awareness Project." The caller discreetly administered a hypochondriasis scale (Pilowsky, 1967) to students who agreed to participate. Respondents who scored two or more standard deviations above the sample mean were excluded from the experiment.

Illness Cognition and Behavior

35

Although the study was conducted in a laboratory suite in a psychology department, the suite was generously supplied with medical paraphernalia such as stethoscopes, blood pressure gauges, eye charts, and health-related posters. Subjects were met at the door by an experimenter wearing a white lab coat. The experimenter told the subjects that they would be administered several medical tests, some quite standard and others very recently developed. The participants also were told that they would be asked to complete some health-related questionnaires. In keeping with the stated purpose of the study, the experimenter then measured each student's pulse and blood pressure. After being seated in individual booths (where subjects were told a hearing test was to be administered later), subjects were told that the next test would be the thioamine acetylase (TAA) saliva reaction test. The test was described in a booklet that the subjects were asked to read while it was read aloud to them over an audio system. The booklet described an enzyme, thioamine acetylase (TAA), which was said to play a role in pancreatic functioning. The booklet indicated that, if present in the body, TAA was found in saliva and other secretory fluids; but while some people had the enzyme, it seemed to be totally lacking in others. The booklet also stated that researchers had recently discovered that people who lack TAA seem to be susceptible to a complex of mild but irritating pancreatic disorders. Fortunately, the booklet stated, if TAA is present in the body, it can be detected in saliva with a chemically coated paper that had been developed about 18 months previous. The booklet next informed subjects how to self-administer the TAA test. First, subjects were told to rinse with a cup of mouthwash (supposedly to cleanse the mouth of any food residue that might contaminate the test). Next, they were told to spit a small amount of saliva into a cup, take out a strip of TAA "test paper," and rub the tip of the test paper in the saliva. Then they were told to wait 30 sec for color development and the result of the test. Unbeknownst to the subjects, the TAA test paper was actually glucosesensitive paper, and a small amount of glucose had been added to their mouthwash. Thus, for all subjects, the test paper turned from its normal yellow color to dark green. This color change was imbued, however, with different diagnostic meanings as a function of experimental condition. Before taking the test, some subjects were told the test paper would turn green if they had TAA deficiency; others were told the opposite, that the test paper would turn from yellow to green if they did not have TAA deficiency. Therefore, subjects saw the same color reaction but were led to interpret that reaction differently. After subjects completed the test, they were asked to answer a series of health-related questionnaires while the experimenter prepared to administer the hearing test. These questionnaires contained the dependent measures.

36

Croyle and Ditto

Questions about TAA deficiency were embedded among questions about other health disorders to mask our special interest in that disorder. As soon as subjects had completed all the dependent measures, they were ushered out of the booths and put through a careful process debriefing (Ross et al., 1975). Subjects were first asked whether they had any questions about the study. During the course of the interview, they were told that TAA did not exist, that the saliva test had been engineered so the test strip always turned green, that the test therefore had no bearing on their susceptibility to pancreatic disease, and that the interpretation they had been given depended only on the experimental condition to which they had been randomly assigned. Subjects were shown the table of random numbers used to assign them to conditions and were allowed to discuss the procedure with other subjects assigned to different conditions. The reasons for the deception were fully explained, any remaining questions were answered, and the subjects were paid and dismissed. Comment on the Procedure

We believe this procedure achieves a good balance between the goals and concerns mentioned earlier. First, the paradigm allows a level of control that cannot be matched with nonexperimental methods. Most importantly, the procedure allows us to vary independently the subjective health status of the subject. In addition, the use of a fictitious health disorder and diagnostic test allows us to observe its effect on an individual's judgments, while holding all other factors (such as previous experience and knowledge) constant. The paradigm also is highly flexible. Within this basic procedure, the researcher can vary virtually any type of information about TAA deficiency (cause, symptoms, course, etc.) and observe its effect on virtually any type of judgment or behavior. One aspect of this flexibility is the capacity to study both self-diagnosis and professional diagnosis. The application to self-diagnosis is especially important because most symptoms and illnesses are dealt with outside the professional sector of care (Chrisman and Kleinman, 1983). The procedure meets the test of experimental realism. Our experience over several studies indicates the procedure is both plausible and involving. During the debriefing, virtually all subjects report being convinced by the procedures: the suspicion rate is low (3-5%). Many subjects report a similarity between the fictitious test and other diagnostic procedures with which they are familiar (e.g., home pregnancy tests, the PTC taste test many students take in science classes). During the initial debriefing, before the deception is revealed, many subjects actively discuss their reaction to the test result with the experimenter or ask for more information about the implications of the

Illness Cognition and Behavior

37

deficiency. And after the deception is revealed, subjects are usually both attentive and curious about the research program as it is described. Finally, several aspects of the procedure reflect the ethical precautions. First, subjects high in hypochondriacal tendencies, who might be most upset by information indicating they were ill, can be excluded from participation. Second, TAA deficiency is not depicted as an extremely serious condition. It is described as a risk factor rather than a disease. In fact, our initial studies indicate that TAA deficiency is generally rated below the midpoint of our seriousness scale, about equal to laryngitis. By comparison, pneumonia, asthma, and anemia are all rated above the midpoint. Third, the time during which the deception is maintained is held to a minimum, typically between 10 and 15 min. Finally, as soon as subjects complete the dependent measures, they are immediately and thoroughly debriefed using measures suggested by Ross et al. (1975) to dispel any lasting effects of experimental manipulations. The subjects generally indicate little if any remaining distress from the procedure. Subjects are unlikely to leave the laboratory concerned about a risk factor they know is fictitious. In fact, most subjects enjoy the opportunity to discuss their views of medicine and diagnostic procedures, often remaining past the allotted time to ask questions or relate previous experiences with physicians and illness.

SUMMARY OF EXPERIMENTS UTILIZING THE PARADIGM Diagnostic Status, Perceived Prevalence, and Threat Appraisal

The design of the first experiment to use the TAA enzyme paradigm was stimulated by the results of a survey of college undergraduates concerning illness beliefs (Jemmott et al., 1988, Study 1). In that study, respondents who had experienced an illness generally rated it as less serious (lifethreatening) than did individuals who had never experienced the condition. Similar findings have been found in surveys of medical patients (Jamison et al., 1986) and their parents (Marteau and Johnston, 1986). Furthermore, Jemmott et al. (1988) reported that perceptions of seriousness were related to beliefs concerning the prevalence of the health disorders. Persons who believed that a symptom or disease was rare tended to view that condition as more life-threatening than did persons who believed the same condition was common. Jemmott et al. conducted a 2 • 2 experiment to test experimentally the relationships observed in the survey. Diagnostic status was manipulated by leading half of the subjects to believe they had TAA deficiency (that the color reaction was a positive test result) and half to believe they did not have

38

Croyle and Ditto

it (that the color reaction was a negative test result). Crossed with this independent variable was the perceived prevalence of TAA deficiency. Although subjects participated in groups of two or three, they were led to believe that five subjects were participating in the session. After subjects had completed the TAA test, they were asked to indicate their test result by flipping on a light in their booth. The manipulation of prevalence was delivered when the experimenter reported to subjects the results of this tally. In the highprevalence condition, the experimenter told the subject that four of the five students had the deficiency. In the low-prevalence condition the subject was told that just one of the five students had the deficiency. The critical dependent measure in the study was the perceived seriousness of TAA deficiency. This question was embedded within a questionnaire asking subjects to rate the seriousness of several health disorders. This list included some disorders that were factual but unfamiliar to the participants (e.g., systemic lupus erythematosus). Subjects were asked to rate each health problem on a 100-point scale, from not serious (can be ignored) to very serious (life-threatening). Both the test result and the perceived prevalence of TAA deficiency were expected to affect perceptions of its seriousness. We expected that a positive test result would induce denial. Although denial and other forms of defensiveness manifest in a variety of ways, minimizing the seriousness of the health threat is one form of denial observed in medical patients (Janis, 1958; Lazarus, 1983; Lipowski, 1970). Clinicians have discussed minimization for decades, but evidence of its occurrence has been largely anecdotal. If minimization results from a motivation to defend the self against threatening information, then individuals who are told they have a health disorder should rate it as less serious than individuals who are told they do not have the disorder. The Jemmott et al. experiment strongly supported this prediction. Subjects who believed they had TAA deficiency appraised it as less life-threatening than did subjects who believed they did not have the deficiency. Another way to deny diagnostic information is to denigrate the methods that produced the evidence. Bad news may lead to a perception of the physician as incompetent or untrustworthy. Or the patient may be motivated to view the medical tests as flawed or improperly administered. The latter form of denial was also apparent in the experiment. Subjects who were told their test results indicated TAA deficiency rated the test as less accurate (on a 9-point scale) than did subjects whose test results indicated that they did not have the deficiency. The tendency to denigrate the accuracy of the test was particularly pronounced when subjects believed that they alone had received a positive test result, further supporting the denial effect. Prevalence information also played a role in subjects' appraisals of the health threat. When subjects believed that only one of five students had tested

Illness Cognition and Behavior

39

positive for TAA deficiency, they perceived the deficiency as significantly more serious than when they believed that four of the five subjects tested positive. This finding held true even though subjects in both conditions received exactly the same information about the medical significance of the condition. This finding is consistent with Zola's (1966) observation that in populations where an ailment is relatively widespread, people are less likely to seek treatment. It is also consistent with the earlier survey showing a reliable negative correlation between people's judgments of the prevalence and seriousness of real health disorders (Jemmott et al., 1988). Finally, the use of prevalence information from an available group of peers provides important empirical support for the role of social comparison information in the interpretation of illness signs (Sanders, 1982).

The Impact of Prevalence Information: Further Insights

Can the effects of prevalence information observed in the Jemmott et al. study provide more general insights into the processes underlying evaluations of our own and othe.~s health characteristics? Ditto and Jemmott (1989) were able to demonstrate that prevalence information has a similar effect on judgments of positive as well as negative health characteristics. In two studies, some subjects were told, as before, that the enzyme condition was a negative health characteristic (that made one more susceptible to pancreatic disease), while others were told that it was a positive health characteristic (that made one less susceptible to pancreatic disease). The prevalence of the characteristic was varied as well. The results indicated that rather than simply leading to more negative appraisals of a medical condition, scarcity information had an extremetizing effect on appraisals. When the enzyme condition was defined as a positive characteristic, it was appraised as more beneficial when it was thought to be rare than when it was thought to be common. When the condition was defined as a negative characteristic, however, perceived rarity served to increase negative appraisals. From these and other data, the authors argued that the effect of prevalence information on evaluations of the seriousness of health disorders comes from our reliance on a simple and general heuristic. This scarcity heuristic is hypothesized to link the perceived prevalence of objects, events, and characteristics to their evaluative extremity. The less prevalent the object of judgment, the more extremely it is evaluated. This research provides an example of how research on illness cognition can provide insights into more general psychological processes. The methods of this investigation are important in the present context for two reasons. First, Ditto and Jemmott used modified versions of one paradigm to demonstrate the same effect in two very different situations. One study used a procedure very similar to that of the Jemmott et al. (1986)

40

Croyle and Ditto

experiment. All subjects tested positive for the enzyme condition, and perceived prevalence was manipulated by altering the number of subjects in the laboratory who supposedly had it. In a second study, subjects simply read a description of the enzyme condition that included summarized prevalence statistics. Similar effects were observed across two levels of self-involvement and with two different prevalence manipulations. The Ditto and Jemmott study also included measures of behavior as well as judgments. After receiving their diagnosis, subjects were given the opportunity to sign up to receive any of a number of informational services regarding the TAA enzyme. The available services consisted of a free pamphlet, a booklet costing 50 cents, and a free physical exam including a complete pancreas workup. Subjects were asked to indicate their interest in receiving these services by checking the appropriate box and leaving their name, address, and telephone number. The number of services each subject requested was summed to form an index of information-seeking behavior. The results indicated that subjects in both diagnostic groups requested more information when the condition was perceived to be rare than when it was perceived to be common. This finding shows that the TAA enzyme paradigm can be used to study elementary illness behavior as well as illness judgments. Denial: Additional Evidence

Ditto et al. (1988) further explored the effects of diagnostic status. Theories of coping suggest that denial and other forms of defensiveness are most likely to occur when an individual has no means of immediately reducing the threat (Janis, 1984; Lazarus, 1983; Leventhal, 1970). To test this notion, Ditto et al. (1988) examined a diagnostic situation where information concerning treatment was immediately available to the "patient." If the minimization observed in the Jemmott et al. experiment was due to motivated denial (as opposed to a rational inference), it is pQssible to derive some counterintuitive predictions concerning the effects of treatment information. A treatable disease is usually perceived as less threatening than an untreatable one (unless the treatment itself is aversive). But if a patient has significantly minimized a threat, evidence that the threat can be reduced in the future may allow the patient to acknowledge its seriousness. Therefore, if motivated denial processes are operating, information indicating that a given disorder is treatable should lead to an increase in how threatening the patient perceives that disorder to be. Ditto et al. followed procedures similar to those used in the Jemmott et ai. study. Half of the subjects were led to believe that they had TAA deficiency and half were led to believe that they did not. But before the enzyme test was conducted, the investigators gave half the subjects additional infor-

Illness Cognition and Behavior

41

mation concerning the treatability of TAA deficiency. Subjects in the treatment-informed condition were told, "Fortunately, treatment for TAA deficiency is relatively simple and painless. A short-term medication program has been found to correct the deficiency in most people by stimulating TAA production." As predicted, the denial effect was most evident among subjects who believed they had the deficiency and were not provided with treatment information. These subjects made a series of judgments that betrayed a relatively optimistic assessment of the meaning of the positive test result. For example, compared to subjects in the other three conditions, positive-result, treatment-uninformed subjects rated the TAA test as less accurate (giving elevated estimates of the test's false positive rate) and both TAA deficiency and pancreatic disease as less life-threatening. In fact, the highest mean rating of the seriousness of pancreatic disease was observed among subjects who believed that they were afflicted with the enzyme deficiency but had been provided with treatment information. The investigators also considered the possibility that denial would be manifested by distortions in perception and memory. In an attempt to measure this process, subjects in the Ditto et al. experiment were asked the color of their " T A A test strip." All test strips turned from yellow to green in response to the sugar in the subject's saliva. On a questionnaire item designed to assess perceptual bias, subjects were asked to recall the color of their test strip and rate it on a 10-point scale (from light green to dark green). Consistent with the other measures of denial, subjects in the positiveresult, treatment-uninformed group tended to remember their test strip as "less green" than other subjects. This perceptual distortion is similar to anecdotal reports from clinical studies. By claiming that the color reaction of the test paper was minimal, these subjects may have concluded that their result indicated a less severe form of the disorder or, perhaps, that their test result was not positive at all. In addition to providing a vivid example of the versatility of self-enhancement strategies, these data also illustrate the importance of measuring any conceptual variable of interest (in this case, denial) in a variety of ways. Effects of Diagnosis on Reports of Symptoms and Risk Behaviors Croyle and Sande (1988) conducted an experiment that served to generalize the TAA enzyme paradigm in two directions. First, the setting was changed. The study was conducted in a formal medical setting, the examination room of a college infirmary. Second, participants in this study did not self-administer the TAA enzyme test. Rather, it was administered by a middle-aged female research assistant dressed in a white lab coat. These

42

Croyle and Ditto

changes were made to increase the similarity between the experimental setting and the typical medical environment-mundane realism. Despite the changes in procedure and context, the results of the earlier studies were replicated. Subjects diagnosed as having TAA deficiency appraised the disorder as a less serious threat to health than did subjects who received negative test results. Furthermore, the former viewed the test as less accurate than did the latter. These findings increase our confidence that the earlier laboratory findings are indicative of real-world reactions to diagnosis. There is an alternative explanation for the minimization effect observed in these studies. In all of the TAA enzyme experiments, the subjects were healthy college students. Participants who were tested for and diagnosed as having TAA deficiency might have discounted the seriousness because they were unable to uncover any symptom experiences associated with the diagnosis. To address this issue, participants in the Croyle and Sande study were asked to complete a symptom checklist after receiving their TAA test result. Subjects were told the symptoms were indicative of TAA deficiency. Contrary to the alternative explanation, Croyle and Sande found that subjects in the positive test result group tended to recall more diagnosisconsistent symptoms than other subjects. Furthermore, positive-result subjects also recalled more behaviors that were said to increase the risk of TAA deficiency. Not only do these data provide further support for the motivated denial explanation of our minimization effects, but also they confirm an important prediction derived from Leventhal's self-regulation model of illness behavior: "Given symptoms, an individual will seek a diagnostic label, and given a label, he or she will seek symptoms" (Leventhal et al., 1980). The experimental demonstration of a diagnosis-induced recall bias also raises further concerns about the validity of self-reports in case control studies in epidemiology (Raphael, 1987).

Replicating the Minimization Effect with Blood Pressure Feedback

Can procedures similar to those described above be used to study psychological reactions to the diagnosis of actual health disorders? If so, are the psychological reactions similar? To explore these questions, Croyle (1990) tested the blood pressure of 40 college students as part of a health survey. Instead of receiving true readings, however, subjects were given false feedback. Half the subjects were told that their pressure was high (140/97). Others were told that their reading was normal (110/80). After receiving this feedback, subjects filled out a brief questionnaire, which included an item concerning their perception of the seriousness of high blood presure. As might be expected from the earlier work, students who received high blood pres-

mness Cognition and Behavior

43

sure feedback rated the condition as a less serious threat to health than did other subjects. These findings were replicated by Croyle in a second sample of students from a different university. Thus, minimization can be observed in the laboratory even for a health disorder as common and familiar as high blood pressure. The effects of labeling on symptom reporting also have been generalized to the domain of blood pressure. Baumann et al. (1989) found confirmatory symptom reporting in an experiment conducted at the University of Wisconsin. Croyle (1990) observed a similar result, but it was confined to male subjects. Collectively, the findings concerning reactions to high blood pressure feedback increase our confidence in the validity of the original TAA enzyme paradigm.

CONCLUSIONS FROM STUDIES TO DATE These laboratory studies are only a first step in the experimental investigation of illness cognition and behavior. However, several insights have been gained regarding some of the motivational and cognitive factors underlying reactions to medical diagnosis. The most consistent finding from the studies reported here is that initial reactions to diagnostic information are often characterized by minimization. Although observational data have previously suggested the operation of this and other denial processes, these studies provide unique experimental evidence of their operation and manifestation. In addition, the data are striking in that the kinds of denial usually attributed to life-threatening stressors are clearly present when individuals are faced with relatively benign health threats. The experimental methodology used here has allowed us to rule out a number of alternative explanations (for details see Croyle and Sande, 1988; Ditto et al., 1988), to replicate the findings in settings varying in mundane realism, and to ellucidate a paradoxical reaction of denial and confirmatory search. In addition, this work supports the development of a mental representational approach to threat appraisal and illness behavior that is generalizable to a variety of situations (Ditto et al., 1988). The second set of findings discussed here concerns the role of the perceived prevalence of a health disorder in the evaluation of its seriousness. Initial illness appraisals appear to be affected by a simple scarcity heuristic, such that the same condition is evaluated in a more extreme fashion when it is relatively rare. Although this general heuristic affects many types of evaluative judgments, it has particularly important ramifications for illness appraisals and behavior. Our data suggest that individuals are influenced even by the prevalence of a health disorder within a small and unrepresentative

44

Croyle and Ditto

comparison group. When the disorder is perceived as common, the individual is less likely to initiate appropriate illness behaviors that are critical for treatment.

FUTURE DIRECTIONS The studies conducted to date only begin to explore the possible uses of the experimental paradigm we have described. Even if we focus only on psychological reactions to medical diagnosis, several avenues for future research are apparent. The areas of study described below have been the subject of field studies using descriptive or correlational designs. In our view, progress in understanding these phenomena might be especially advanced by experimental research using the TAA enzyme paradigm. The Relationship Between Minimization and Illness Behavior It is tempting to assume a simple one-to-one relationship between appraisals of a health threat and behavior in response to it. In the case of minimization and other forms of denial, it is often assumed that the motivated downplaying of the seriousness of an illness or of a diagnostic test's accuracy inevitably interferes with appropriate coping behavior (Haan, 1977; Kroeher, 1963). Other researchers have suggested that minimization processes may sometimes facilitate action-oriented coping by reducing arousal to a level that is less likely to interfere with appropriate treatment or information-seeking behavior (Cohen and Lazarus, 1979; Lazarus, 1983; Suls and Fletcher, 1985). The latter researchers suggest a more complex appraisal-behavior relationship in which relatively benign appraisals may not always be associated with a diminished likelihood of engaging in palliative measures. The present paradigm would seem quite useful for examining this issue. Factors leading to minimization can be varied and both appraisals and information-seeking behavior can be measured. A variety of questions can be examined with this approach. For example, in what circumstances does minimization interfere with appropriate action? Do some forms of denial interfere with or facilitate action more than others? Is the appraisal-behavior relationship different for different people? Memory for Diagnostic Information The efficacy of medical care depends to a great extent on the patients' recall of information and recommendations provided by the physician. Sub-

Illness Cognition and Behavior

45

stantial evidence, however, indicates that patients have poor recall for information conveyed by their physicians (Ley, 1979), perhaps one reason for the low rates of satisfaction and compliance frequently observed in patients. Experimental psychologists can contribute a great deal to an understanding of this problem. Until recently, however, the methods of cognitive and health psychology had little in common (Skelton and Croyle, 1990). By bringing the diagnostic situation into the laboratory, experimental techniques of investigation can be utilized to their fullest. In addition to providing new details concerning the rate at which diagnostic information is forgotten, this work also can document differential rates of forgetting across the various kinds of information conveyed in a diagnostic interview. Which is better recalled, cause or prognosis? How does level of threat relate to memory deficits? What is the relationship between emotional reactions to diagnosis and recall? The study of memory in this context also should provide further insights into the minimization processes discussed earlier. While clinical researchers have related memory dysfunction to denial, we know very little about the processes underlying these phenomena. Often, poor recall is viewed as prima facie evidence for denial. By measuring appraisals with more precision and specificity, judgment-related consequences of diagnosis (like minimization) can be distinguished from forgetting. The experimental setting also provides a cost-effective means of testing the efficacy of interventions intended to improve recall. The first author is exploring the memory issue within the context of cholesterol screening. But the TAA enzyme paradigm also can be used to answer many questions concerning the effects of diagnostic labels on basic cognitive processes. By using a paradigm where subjects are exposed to a label about which they have no prior knowledge or experience, investigators can study information acquisition processes with greater experimental control.

The Role of Affect in Mediating Responses to Diagnosis

Recent evidence indicates mood can have a significant effect on selfappraisals of health status and on risk assessment (Croyle and Uretsky, 1987; Johnson and Tversky, 1983; Katon, 1984). An individual's affective reactions to diagnosis might mediate cognitive and behavioral reactions. Hopp and Croyle (1989) provided some evidence for this hypothesis. They found that subjects who experienced negative affect after a fingerprick cholesterol test were less likely to recall nutrition information presented after their test result. Mood also can influence the self-appraisal of health status. Croyle and Uretsky (1987) tested the effects of mood on health-related judgments

46

Croyle and Ditto

and recall by inducing a positive or negative mood. Subjects viewed a videotape containing either humorous or depressing scenes from popular movies. Subjects then participated in what they believed was an unrelated health survey. Those who viewed the depressing videotape reported more symptoms for the previous 30 days than did other subjects. They also made more negative appraisals of their current health status. The TAA enzyme paradigm provides one context within which to explore the relationships among cognitive appraisal, emotional reactions and coping behaviors. These relationships are likely to be complex, because appraisal may initiate affect which is later regulated by reappraisal (Lazarus and Folkman, 1984). Our experience suggests that affect may be the most difficult component to measure in a nonreactive way. Because of possible biases in self-reports of mood, future studies employing the enzyme paradigm should rely on less obtrusive measures. Several investigators have assessed affect in other contexts by videotaping the facial expressions of subjects (e.g., Carlson and Masters, 1986). Another investigative strategy would be to test experimentally the effects of prior mood state on reactions to diagnosis. Finally, an understanding of the emotional processes underlying illness behavior in the diagnostic context will depend on further insights concerning the role of expectancies. Because expectations influence both information processing (Markus and Zajonc, 1985; Snyder, 1984) and emotional reactions, we believe them to be an important determinant of an individual's reaction to diagnostic information. The Practitioner-Patient Relationship Numerous studies have examined the nature and quality Of practitionerpatient relationships (Taylor, 1986). The paradigm described here provides a context in which to test variables seen to be important in these interactions. Because the behavior of an experimenter can be controlled more carefully than the behavior of physicians in a field study, greater experimental rigor can be obtained. Characteristics of the test administrator can be varied as well as the style and content of practitioner-patient communications. Two of the factors that might be easily varied in the current paradigm are the practitioner's status (physician, nurse, assistant) and the practitioner's interaction style. For example, in a recent study by Kalish et al. (1988), individuals with preferences for particular "types" of physicians (i.e., an "authoritarian" physician who provides answers vs a more "egalitarian" physician who discusses options) read descriptions of an interaction with a physician who either matched or did not match their preferences. Compared to matched subject-physician pairs, mismatched subjects indicated not only that they liked the physician described in the vignette less, but also that they would

Illness Cognition and Behavior

47

be less likely to follow the treatment regimen prescribed by the physician. The TAA paradigm could be used to examine whether similar effects occur in a live interaction. By videotaping these interactions, numerous insights might be gained into the ways patients respond to health care practitioners. Observers' Reactions to Medical Diagnosis One determinant of self-appraisal that seems especially important to the social psychological aspects of health and illness is social comparison (Festinger, 1954; Sanders, 1982). Individuals are motivated to compare their health status with others, especially when the meaning of symptoms is ambiguous. Comparison with less healthy others is one means of coping with a health problem (Wills, 1987; Taylor et al., 1984). By testing groups of subjects in the TAA enzyme paradigm, it should be possible to examine the role of social comparison and social influence in the appraisal process. In addition, the study of social comparison processes is related to the study of social support, a topic that has caught the attention of an increasing number of psychologists (Cohen and Syme, 1985; Sarason and Sarason, 1985). Most studies of social support have used surveys as a means of testing hypotheses; few studies have examined support experimentally (Sarason and Sarason, 1986). By giving subjects an opportunity to provide social support to a fellow subject or confederate who has received threatening diagnostic information, investigators can examine the ways people try to comfort disease victims. Individual differences in expressing empathy and delivering support also might be examined. At least one study (Gruman and Sloan, 1983), for example, suggests that individuals who believe in a "just world" are more likely to derogate victims of disease. Finally, a variety of issues regarding the effects of social support can be examined. For example, the effects of social support may not always be beneficial (Rook, 1984; Suls, 1982). The TAA enzyme paradigm may be useful in determining when supporting others will increase the victim's likelihood of taking appropriate palliative action and when it might interfere with such behavior.

LIMITATIONS OF THE PARADIGM The advantages of experimental control are well known. Nevertheless, the kind of experimental research discussed here is no substitute for clinical research on medical patients or descriptive research using larger subject samples. This experimental paradigm is best suited for studying a particular class of disorders, those that are less severe and mostly asymptomatic. For exam-

48

Croyle and Ditto

pie, while many field studies of illness behavior have focused on chronic pain patients (Feuerstein et ai., 1986), the research techniques described here may have less relevance to cases where pain is the significant feature. Field studies of coping also have focused on extremely serious disorders such as cancer and myocardial infarction (Taylor, 1986). The experimental manipulation of an individual's subjective health status at a level comparable to these disorders is ethically untenable. While the study of appraisals of less serious disorders and those that are relatively asymptomatic may depart from the traditional focus of clinical investigators, one of our goals in developing the paradigm was to broaden the scope of study to include appraisals of those types of conditions. The advantage is that the artificial aspects of the procedure favor the null hypothesis; any effects we obtain are at worst an underestimate of the effects produced in the medical setting. For some contexts, such as cholesterol screening and other kinds of risk factor testing, direct generalizations from our findings may be possible. The primary utility of an experimental paradigm, however, is as a tool for theory testing and process analysis. One task of future research will be to determine the degree to which the psychological processes underlying illness cognition and behavior vary as a function of the severity of the condition. Our own research suggests that the similarities may outweigh the differences. Ethical concerns also dictate that the analog approach can only examine initial reactions to health threats. The necessarily limited time frame of deception research rules out studies of how appraisals may change over time or of how people cope with chronic or recurring diseases. Longitudinal research conducted by Lehman (Lehman et al., 1987) and others has shown that theoretical propositions based on the study of short-term impact may not necessarily generalize to the long term. As Suls and Fletcher (1985) have shown, the efficacy of coping strategies also appears to be time dependent. Nevertheless, we believe that the experimental work discussed here begins to shed light on short-term reactions to diagnosis, an area that has been largely neglected by empirical research. Finally, this paradigm has, to this point, been used only in research on college students. Whenever one group serves as the focus of study, care should always be taken before results are generalized to a broader population. Logistical and ethical concerns have made college students the most attractive and accessible subjects for this research. As long as basic psychological processes are the focus, this limitation is not serious. A number of studies that have examined health-related judgments have found similar results across college student and community samples (e.g., Weinstein, 1982, 1987). Furthermore, college students are an important population in their own right. The application of risk factor screening to this age group is increasing. As we move from judgments to behaviors, however, more signifi-

Blness Cognition and Behavior

49

cant differences are likely to emerge. A young and healthy population can react quite differently to threatening health situations than an older population more experienced with illness (Leventhal et al., 1987). Nevertheless, it is important that assumed differences between populations be derived from empirical observation and theoretically driven hypotheses instead of stereotypes.

CONCLUSION Results of several investigations using an experimental paradigm for the study of illness cognition and behavior indicate the method is a useful tool for uncovering some of the processes underlying psychological reactions to health threats. Subjective diagnostic status was found to be an important determinant of a wide variety of health-related judgments. The method also provides a cost-effective way of testing possible methods of intervention in doctor-patient interactions. We hope this presentation encourages other investigators to employ the methods of cognitive and social psychology in investigating health-relevant behavior. Experimental research can provide critical corroborating evidence for theoretical propositions until now supported only by correlational data. Conversely, experiments themselves can generate interesting hypotheses to test and generalize in more naturalistic settings. Experimental and nonexperimental methodologies have nonoverlapping strengths and weaknesses. Laboratory experiments tend to have high internal validity and somewhat lower external validity. They also are limited by ethical and logistical concerns to the study of certain populations and stimuli. Correlational, clinical, and field studies, on the other hand, often may have greater external validity with a correspondent loss of internal validity. Field studies also tend to be less constrained in their scope of investigation. Ideally then, the two methodologies are complementary: research with one should be used to test and expand on hypotheses generated by the other, particularly in the study of illness cognition and behavior. Only by using a variety of research techniques and theoretical perspectives will we obtain a thorough understanding of how people think about their health and cope with their illnesses.

ACKNOWLEDGMENT The authors thank John Jemmott for his numerous contributions to the research discussed in this paper.

50

Croyle and Ditto

REFERENCES Aronson, E., Brewer, M., and Carlsmith, J. M. (1985). Experimentation in social psychology. In Lindzey, G., and Aronson, E. (eds.), The Handbook of Social Psychology, 3rd ed., Vol. I, Random House, New York, pp. 441-486. Barondess, J. A. (1979). Disease and illness-A crucial distinction. Am. J. Med. 66: 375-376. Barsky, A. J., and Klerman, G. L. (1983). Overview: Hypochondriasis, bodily complaints and somatic styles. Am. J. Psychiat. 140: 273-283. Banmann, L. J., Cameron, L. D., Zimmerman, R. S., and Leventhal, H. (1989). Illness representations and matching labels with symptoms. Health Psychol. 8: 449-469. Bloom, J. R., and Monterossa, S. (1981). Hypertension labeling and well-being. Am. J. Public Health 71: 1228-1232. Bulman, R. J., and Wortman, C. B. (1977). Attributions of blame and coping in the "real world": Severe accident victims react to their lot. J. Personal. Soc. Psychol. 35: 351-363. Carlsmith, J. M., EUsworth, P. C., and Aronson, E. (1976). Methods of Research in Social Psychology, Addison-Wesley, Reading, MA. Carlson, C. R., and Masters, J. C. (1986). Inoculation by emotion: Effects of positive emotional states on children's reactions to social comparison. Dev. Psychol. 22: 760-765. Chrisman, N. J., and Kleinman, A. (1983). Popular health care, social networks, and cultural meanings: The orientation of medical anthropology. In Mechanic, D. (ed.), Handbook of Health, Health Care, and the Health Professions, Free Press, New York, pp. 569-590. Cohen, F., and Lazarus, R. S. (1979). Coping with the stresses of illness. In Stone, G. C., Cohen, F., and Adler, N. E. (eds.), Health Psychology--A Handbook, Jossey-Bass, San Francisco, pp. 217-254, Cohen, S., and Syme, L. (eds.) (1985). Social Support and Health, Academic Press, New York. Croog, S. H., Shapiro, D. S., and Levine, S. (1971). Denial among heart patients Psychosom. Med. 33: 385-397. Croyle, R. T. (1990). Biased appraisal of high blood pressure. Prey. Med. (in press). Croyle, R. T., and Sande, G. N. (1988). Denial and confirmatory search: Paradoxical consequences of medical diagnosis. J. Appl. Soc. Psychol. 18: 473-490. Croyle, R. T., and Uretsky, M. B. (1987). Effects of mood on self-appraisal of health status. Health Psychol. 6: 239-253. Ditto, P. H., and Jemmott, J. B. (1989). From rarity to evaluative extremity: Effects of prevalence information on the evaluation of positive and negative characteristics. J. Personal. Soc. Psychol. 57: 16-26. Ditto, P. H., Jemmott, J. B., and Darley, J. M. (1988). Appraising the threat of illness: A mental representational approach. Health Psychol. 7: 183-200. Festinger, L. (1954). A theory of social comparison processes. Hum. Relat. 7: 117-140. Feuerstein, M., Labb~, E. E., and Kuczmierczyk, A. R. (1986). Health Psychology: A Psychobiological Perspective, Plenum, New York. Gruman, J. C., and Sloan, R. P. (1983). Disease as justice: Perceptions of the victims of physieal illness. Basic Appl. Soc. Psychol. 4: 39-46. Haan, N. (1977). Coping and Defending: Processes of Self-Environment Organization, Academic Press, New York. Hampton, M. L., Anderson, J., Lavizzo, B. S., and Bergman, A. B, (1974). Sickle cell "nondisease": A potentially serious public health problem. Am. J. Dis. Child. 128: 58-61. Hopp, H. P., and Croyle, R. T. (1989). Reactions to risk factor labeling: The role of affect. Presented at the Annual Meeting of the Midwestern Psychological Association, Chicago, May. Jamison, R. N., Lewis, S., and Burish, T. G. (1986). Psychological impact of cancer on adolescents: Self-image, locus of control, perception of illness and knowledge of cancer. J. Chron. Dis. 39: 609-617. Janis, I. L. (1958). Psychological Stress, Wiley, New York. Janis, I. L. (1984). Improving adherence to medical recommendations: Prescriptive hypotheses derived from recent research in social psychology. In Baum, A., et al. (eds.), Handbook of Psychology and Health, Vol. IV, Erlhaum, Hillsdale, NJ, pp. 113-148.

lllness Cognition and Behavior

51

Jemmott, J. B., Ditto, P. H., and Croyle, R. T. (1986). Judging health status: Effects of perceived prevalence and personal relevance. J. Person. Soc. Psychoi. 50: 899-905. Jemmott, J. B., Croyle, R. T., and Ditto, P. H. (1988). Commonsense epidemiology: Selfbased judgments from laypersons and physicians. Health Psychol. 7: 55-73. Johnson, E., and Tversky, A. (1983). Affect, generalization, and the perception of risk. J. Person. Soc. Psychol. 36: 236-246. Kalish, J., Hilton, J. L., and Ditto, P. H. (1988). The effects of patients' expectations and physicians' communication styles on doctor-patient interactions. Unpublished manuscript, University of Michigan, Ann Arbor. Kasl, S. V., and Cobb, S. (1966). Health behavior, illness behavior and sick role behavior. Arch. Environ. Health 12: 246-266. Katon, W. (1984). Depression: Relationship to somatization and chronic medical illness. J. Clin. Psychiat. 45 (3; Sect. 2): 4-11. Kroeber, T. C. (1963). The coping functions of the ego mechanism. In White, R. W. (ed.), The Study of Lives, Prentice-Hall, Englewood Cliffs, NJ. Lazarus, R. S. (1983). The costs and benefits of denial. In Breznitz, S. (r The Denial of Stress, International Universities Press, New York, pp. 1-30. Lazarus, R. S., and Folkman, S. (1984). Stress, Appraisal, and Coping, Springer, New York. Lehman, D. R., Wortman, C. B., and Williams, A. F. (1987). Long-term effects of losing a spouse or child in a motor vehicle crash. J. Person. Soc. Psychol. 52: 218-231. Leventhal, H. (1970). Findings and theory in the study of fear communications. In Berkowitz, L. (ed.), Adv. Exp. Soc. Psychol. Vol. 3, Academic Press, New York, pp. 120-186. Leventhal, H. (1986). Symptom reporting: A focus on process. In McHugh, S., and Vallis, T. M. (eds.), Illness Behavior: A Multidisciplinary Model. Plenum, New York, pp. 219-237. Leventhal, H., Leventhal, E., and Schaefer, P. (1987). Seeking health care: The wisdom of vigilant coping. Presented in Illness Appraisal: Social and Cognitive Processes (Chaired by Croyle, R. T.). Symposium at the meeting of the Midwestern Psychological Association, Chicago, May 1987. Leventhal, H., Meyer, D., and Nerenz, D. (1980). The commonsense representation of illness danger. In Rachman, S. (ed.), Medical Psychology, 2, Pergamon, New York. Ley, P. (1979). Memory for medical information. Br. J. Soc. Clin. Psychol. 18: 245-255. Lipowski, Z. J. (1970). Physical illness, the individual and the coping process. International. J. Psychiat. Med. 1: 91:102. Markus, H. M., and Zajonc, R. B. (1985). The cognitive perspective in social psychology. In Lindzey, G., and Aronson, E. (eds.), The Handbook of Social Psychology, VoL 1, Erlbaum, Hillsdale, NJ. Marteau, T. M., and Johnson, M. (1986). Determinants of beliefs about illness: A study of parents of children with diabetes, asthma, epilepsy, and no chronic illness. J. Psychosom. Res. 30: 673-683. Mechanic, D. (1972). Social psychologic factors affecting the presentation of bodily complaints. N. Engl. J. Med. 286: 1132-1139. Pennebaker, J. (1982). The Psychology of Physical Symptoms, Springer-Verlag, New York. Pilowsky, I. (1967). Dimensions of hypochondriasis. Br. J. Psychiat. 113: 89-93. Pilowsky, I. (1969). Abnormal illness behavior. Br. J. Med. Psychol. 42: 347-351. Raphael, K. (1987). Recall bias: A proposal for assessment and control. Int. J. Epidemiol. 123: 670-676. Rook, K. S. (1984). The negative side of social interaction: Impact on psychological well-being. J. Person. Soc. PsychoL 46: 1097-1108. Ross, L., Lepper, M., and Hubbard, M. (1975). Perseverance in self perception and social perception: Biased attributional processes in the debriefing paradigm. J. Person. Soc. Psychol. 32: 880-892. Sanders, G. S. (1982). Social comparison and perceptions of health and illness. In Sanders, G. S., and Suls, J. (eds.), Social Psychology of Health and Illness, Erlbaum, Hillsdale, NJ, pp. 129-157. Sarason, I. G., and Sarason, B. R. (1985). Social Support: Theory, Research, and Applications, Martinus Nijhoff, Boston.

52

Croyle and Ditto

Sarason, I. G., and Sarason, B. R. (1986). Experimentally provided social support. 3". Person. Sac. Psychol. 50: 1222-1225. Skelton, J. A., and Croyle, R. T. (eds.) (1990). The Mental Representation of Health andlIIhess, Springer.Verlag, New York (in press). Snyder, M. (1984). When belief creates reality. In Berkowitz, L. (ed.), Adv. Exp. Sac. Psychol. Vol. 18, Academic Press, New York. Suls, J. (1982). Social support, interpersonal relations, and health: Benefits and liabilities. In Sanders, G. S., and Suls, J. (eds.), Social Psychology of Health and Illness, Erlbaum, Hillsdale, NJ., pp. 255-278. Suls, J., and Fletcher, B. (1985). The relative efficacy of avoidant and nonavoidant coping strategies: A meta-analysis. Health Psychol. 4: 249-288. Taylor, S. E. (1986). Health Psychology, Random House, New York. Taylor, S. E., Lichtman, R. R., and Wood, J. V. (1984). Attributions, beliefs about control, and adjustment to breast cancer. J. Person. Sac. Psychol. 46: 489-502. Turnquist, D. C., Harvey, J. H., and Anderson, B. L. (1988). Attributions and adjustment to life-threatening illness. Br. J. Clin. Psychol. 27: 55-65. Watson, M., Greet, S., Blake, S., and Shrapnell, K. (1984). Reactions to the diagnosis of breast cancer: Relationship between denial, delay and rates of psychological morbidity. Cancer 53: 2008-2012. Weinstein, N. D. (1982). Unrealistic optimism about susceptibility to health problems. J. Behav. Med. 5: 441-460. Weinstein, N. D. (1987). Unrealistic optimism about susceptibility to health problems: Conclusions from a community-wide sample. J. Behav. Med. 10: 481-500. Wills, T. A. (1987). Downward comparison as a coping mechanism. In Snyder, C. R., and Ford, C. E. (eds.), Coping with Negative Life Events, Plenum, New York, pp. 243-268. Zola, I. K. (1966). Culture and symptoms-an analysis of patients' presenting complaints. Am. Sociol. Rev. 31: 615-630.