The efficiency of a new strategy to identify back random responding (BRR) on the Personality Assessment Inventory (L. C. Morey, 1991) was studied using random manipulations of item responses from community (904 adult nonpatients) and clinical (1,079 adult patients) respondents. The strategy involved a comparison of short-form and full-instrument T scores on 2 scales found to be particularly sensitive to BRR in a recent study. This strategy was found to be reasonably sensitive and specific to even relatively low levels of BRR.