Detection of back random responding: effectiveness of MMPI-2 and Personality Assessment Inventory validity indices.

Two experiments examined the detection and effects of back random responding (BRR) on the Minnesota Multiphasic Personality Inventory--2 (MMPI-2) and the Personality Assessment Inventory (PAI). Experiment 1 revealed that MMPI-2 Clinical and Content scales were relatively resistant to the effects of BRR. Fb--F > or = 20T was the most effective index for identifying invalid protocols. Experiment 2 revealed greater susceptibility of the PAI interpretive scales to the effects of BRR and less successful detection of BRR. The most effective PAI validity index was the combined indicator, ICN > or = 73T or INF > or = 75T. Clinical and empirical implications of these findings are discussed, and tentative modifications to the MMPI-2 interpretative guidelines are provided.