The treatment utility of assessment. A functional approach to evaluating assessment quality.

" In practical terms, the sine qua non of the modes, methods, devices, strategies, and theories of clinical assessment is their contribution to treatment outcome. The importance of this contribution has often been noted, but under many different labels and rationales. The resultant conceptual confusion has considerably restricted the visibility and frequency of research in this critical area. In this article we propose a name for the impact of assessment on treatment outcome: the "treatment utility of assessment. "' Some of the questions that can be asked about the treatment utility of assessment are described, and methods appropriate for asking them are examined. Finally, the implications of this kind of utility for other approaches to evaluating assessment quality are analyzed. Clinical assessment is an important and fertile area of psychology, and yet there is general agreement that it has not been in a state of continuous and healthy growth (e.g., Bersoff, 1973; Korchin & Schuldberg, 1981; Rorer & Widiger, 1983). Compared to the early days of clinical psychology, there has been a decline in the emphasis on clinical assessment both in training and in practice (Garfield & Kurtz, 1973, 1976; Levitt, 1973; Shemberg & Keeley, 1970). One reason may be that clinical assessment has not yet proven its value in fostering favorable treatment outcomes. As clinical psychologists have devoted more and more time to treatment activities, the practical value of assessment has come under closer scrutiny (McReynolds, 1985). Unfortunately, experienced clinicians have not always found assessment data to be useful in treatment (Adams, 1972; Daily, 1953; Meehl, 1960; Moore, Bobbitt, & Wildman, 1968). Even the proponents of clinical assessment admit that "we do not believe that the current [high] status of testing is due to its demonstrated value" (Kaplan, Colarelli, Gross, Leventhal, & Siegel, 1970, p. 15). The lack of empirical evidence for the practical value of assessment has long been noted. In 1959, Meehl pointed out that, even if an assessment procedure is reliable and valid, a clinician might "be seriously in error if he concluded therefrom that his tests were paying o f f in practice. On this question there i s . no published empirical evidence" (p. 117). Twenty-two years later, Korchin and Schuldberg (1981) were still worried that "clinical assessment may not provide the kind of information needed by therapists. Objective evidence is slim" (p. 1154). More recently, McReynolds (1985) asked "Are tests helpful to the therapist? Amazingly, there has been little research on this crucial question" (p. 10). The purpose of the present article is to consider how to make better progress in understanding the role of assessment in successful treatment. Any lack of evidence on the clinical value of assessment is not caused by a lack of appreciation for its ultimate practical purposes. Korchin (1976) defined clinical assessment as "the process by which clinicians gain understanding of the patient necessary for making informed decisions" (p. 124). Thus, the "basic justification for assessment is that it provides information of value to the planning, execution and evaluation of treatment" (Korchin & Schuldberg, 1981, p. 1154). Wiggins (1973) said, "Although measurement and prediction may be evaluated by formal psychometric criteria, such as reliability and validity, the outcomes of [assessment] decisions must be evaluated in terms of their utilities for individuals and institutions within our society" (p. 272, emphasis in original). Meehl (1959) phrased it as follows: "In what way and to what extent does t h i s . , information help us in treating the patient? " (1959, p. 117). He called this question "ultimately the practically significant one by which the contributions of our [assessment] techniques must be judged" (p. 116). Definition of the Treatment Utility of Assessment The impact of clinical assessment on treatment outcome has been discussed under a wide variety of labels. Among other terms, it has been viewed as a matter of incremental validity (Mischel, 1968), concurrent validity (Meehl, 1959), construct validity (Edwards, 1970), predictive validity (Lord & Novick, 1968), discriminative efficiency (Wiggins, 1973), and utility (Cronbach & Gleser, 1965). There is considerable confusion about the concepts relevant to the measurement of pragmatic clinical value. We propose to use the phrase the treatment utility of assessment to refer to the degree to which assessment is shown to contribute to beneficial treatment outcome, l 1 Earlier (Nelson & Hayes, 1979), we had used the term treatment validity. Although utility issues can indeed be considered an aspect of validity, the present term seems more direct. November 1987 9 American Psychologist Copyright 1987 by the American Psychological Assooation, Inc. 0003-066X/87/$00.75 Vol. 42, No. I I, 963-974 963 An assessment device, distinction, or strategy has this kind of utility if it can be shown that treatment outcome is positively influenced by this device, distinction, or strategy. The treatment utility of assessment deserves to be termed a type of utility because it relates closely to the functional thrust of that psychometric term. The need to qualify the word utility with the adjective treatment is justified by two facts. First, utility has been almost exclusively evaluated in terms of personnel decisions (e.g., Wiggins, 1973). The issues and methods involved in demonstrating the impact of assessment on treatment outcomes differ significantly from the methods appropriate to the analysis of personnel decisions. Second, in personnel matters the concept of utility has come to refer primarily to the cost-benefit ratio of assessment strategies. This is why it was originally distinguished from predictive validity (Mischel, 1968). The treatment utility of assessment is not primarily a matter of cost-benefit analysis but of the demonstration of a particular type of benefit. Barriers to Research on the Treatment Utility of Assessment Theorists have long believed that research on the treatment utility of assessment should be feasible. "It is well within the capacity of available research methods and clinical facilities to determine what, if any, is the pragmatic advantage of a personality assessment" (Meehl, 1959, p. 125). Why then has there continued to be so little research? There are several possible reasons. First, because of conceptual confusion about the psychometric concepts relevant to the treatment utility of assessment, little has been written about the kinds of methods appropriate to treatment utility questions. In the present article, we present a taxonomy of treatment utility methods in the hope of alleviating this problem. Second, "Clinical p s y c h o l o g i s t s . , often make a sharp cleavage between their roles as diagnostician and therapist" (Blatt, 1975, p. 336). Assessment is often not integrated into the therapy process. When the two are disconnected, the value of assessment seemingly turns on the question, Is this diagnosis correct? not Is this assessment useful in treatment? Some clinicians even fear that the assessment process is negatively intrusive on the therapeutic alliance. By focusing on the contribution of assessment to treatment outcome, treatment utility provides an approach for the testing of such concerns and may itself help integrate assessment and treatment roles. Another part of the problem may lie in the belief that complete psychometric purity is necessary before the treatment utility of assessment can be shown or even examined. Wiggins (1973), who has emphasized the The authors would like to thank Paul McReynolds for his helpful comments on an earlier draft of this article. Correspondence concerning this article should be addressed to Steven C. Hayes, Department of Psychology, University of Nevada-Reno, Reno, NV 89557-0062. practical importance of assessment more than most psychometric theorists, noted the possibility that "concern with the technical problems of measurement . has resulted in a relative neglect of the broader context in which such problems arise, namely, the optimal assignment of men to jobs or treatments" (p. 272). As we will show, there seems to be little reason to delay treatment utility research until psychometrically perfect devices are