Minimizing False Positive Error With Multiple Performance Validity Tests: Response to Bilder, Sugar, and Hellemann (2014 this issue)

Abstract

Bilder, Sugar, and Hellemann (2014 this issue) contend that empirical support is lacking for use of multiple performance validity tests (PVTs) in evaluation of the individual case, differing from the conclusions of Davis and Millis (2014), and Larrabee (2014), who found no substantial increase in false positive rates using a criterion of failure of ≥ 2 PVTs and/or Symptom Validity Tests (SVTs) out of multiple tests administered. Reconsideration of data presented in Larrabee (2014) supports a criterion of ≥ 2 out of up to 7 PVTs/SVTs, as keeping false positive rates close to and in most cases below 10% in cases with bona fide neurologic, psychiatric, and developmental disorders. Strategies to minimize risk of false positive error are discussed, including (1) adjusting individual PVT cutoffs or criterion for number of PVTs failed, for examinees who have clinical histories placing them at risk for false positive identification (e.g., severe TBI, schizophrenia), (2) using the history of the individual case to rule out conditions known to result in false positive errors, (3) using normal performance in domains mimicked by PVTs to show that sufficient native ability exists for valid performance on the PVT(s) that have been failed, and (4) recognizing that as the number of PVTs/SVTs failed increases, the likelihood of valid clinical presentation decreases, with a corresponding increase in the likelihood of invalid test performance and symptom report.

Keywords:

• Performance and symptom validity tests
• Multiple scores
• False positive rate.

Acknowledgments

Preparation of this rebuttal was coordinated with the comments prepared by Drs. Davis and Millis (2014 this issue), to minimize redundancy. Dr. Larrabee provides forensic consultation to attorneys in litigated matters. He receives royalties from Psychological Assessment Resources for sales of the Continuous Visual Memory Test, and receives royalties from Oxford University Press for sales of the book, Assessment of Malingered Neuropsychological Deficits.