Do Psychotherapists Use a Confirmatory Strategy During Interviewing?

This study examined whether psychotherapists test hypotheses about others by preferentially sampling hypothesis-congruent as opposed to hypothesis-disconfirming information. Psychotherapists interviewed normal college undergraduates attempting to assess introversion-extraversion. The results suggested that psychotherapists preferentially sampled behavioral evidence that would confirm their hypotheses when they chose questions from a pre-existing list, but not when they design their own questions. Additionally, in the condition where therapists preferentially exhibited the confirmatory tendency, there was a self-fulfilling impact on the behavior of interviewees. According to blind judges, the latter came to behave in a manner that would appear to confirm the hypotheses under investigation. Finally, therapists' ratings of interviewees did not reflect these behavioral changes. The relevance of these results to the clinical setting is discussed.