Confidence in psychodiagnosis : a study of clinicians' judgement confidence in a psychological assessment task as a function of reliance on four inferential heuristics and clinical experience

Research in several domains has revealed that when individuals are asked to estimate the probability that their judgments are correct, they reveal an overconfidence effect. Judgments produced in decision environments such as psychodiagnosis, which are by their nature ambiguous and complex, appear to be most vulnerable to overconfidence. By implication, this phenomenon threatens the validity of clinical judgment and subjects clients to risks of flawed diagnoses and unsuitable treatments.In an effort to identify variables implicated in judgment confidence and overconfidence, this study examined the relationship between four different inferential biases (dispositionalism, confirmationism, truncated data search, and narrow problem formulation) and diagnostic confidence in the context of a psychological assessment task. A second aspect of this study examined the effect of clinical experience on psychodiagnostic confidence. Thirty-six clinicians (18 experienced professionals and 18 clinical trainees) were individually presented a written client casefile, which was segmented and serially presented, to read and clinically interpret aloud. Analyses of participants' verbal protocols revealed that one of the four inferential biases studied (i.e., dispositionalism) accounted for a significant proportion of the variance in psychodiagnostic confidence scores. The author concludes that other clinician variables likely moderate the relationship between particular heuristics and judgment confidence. Regarding the second hypothesis, the data revealed no difference between experienced clinicians and clinical trainees in the degrees of psychodiagnostic confidence manifested in their verbal protocols.The author proposes that effective remedies to overconfidence begin in training programs that lead students through problem-solving experiences that can invalidate facile, premature, and dubious diagnostic judgments. The author delineates a number of strategies that may be used by educators to achieve this end