Self-Report Measures of Anhedonia and Approach Motivation Weakly Correspond to Anhedonia and Depression Assessed via Clinical Interviews.

Self-report scales are popular tools for measuring anhedonic experiences and motivational deficits, but how well do they reflect clinically significant anhedonia? Seventy-eight adults participated in face-to-face structured diagnostic interviews: 22 showed clinically significant anhedonia, and 18 met criteria for depression. Analyses of effect sizes comparing the anhedonia and depression groups to their respective controls found large effects, as expected, for measures of depressive symptoms, but surprisingly weak effect sizes (all less than d=.50) for measures of general, social, or physical anhedonia, behavioral activation, and anticipatory and consummatory pleasure. Measures of Neuroticism and Extraversion distinguished the anhedonic and depressed groups from the controls at least as well as measures of anhedonia and motivation. Taken together, the findings suggest that caution is necessary when extending self-report findings to populations with clinically significant symptoms.