Detecting Simulated Memory Impairment with the Rey Auditory Verbal Learning Test: Implications of Base Rates and Study Generalizability

Abstract

The accuracy of the Rey Auditory Verbal Learning Test (RAVLT) for detecting simulated neuropsychological impairment was investigated using discriminant function analyses and cross-validation procedures. In Study 1, a discriminant function analysis, using six RAVLT variables, correctly classified 80% of 50 simulating and 50 non-simulating participants. Base rates were changed and this discriminant function was tested in Study 2 with a 33% base rate of simulation. The discriminant function correctly classified 75% of 20 simulators and 90% of 40 non-simulators, yielding an overall classification rate of 85%. To determine the generalizability of this discriminant function to a clinical sample, Study 3 compared the RAVLT performance of 20 simulating participants to that of 40 motor vehicle accident (MVA) patients. The discriminant function from Study 1 incorrectly classified 60% of the MVA patients and yielded an overall correct classification rate of 48%. The limitations associated with generalizing from analog research and the implications of varying base rates on classification accuracy are discussed.