Abstract

Objective

We compared valid or invalid SIMS performance to other performance and symptom validity measures.

Methods

Data from 119 forensic neuropsychological evaluations [competency (n = 106), forensic (n = 5), insanity (n = 5), commitment review (n = 2), and danger (n = 1)] were analyzed. Three chi-squares tests compared group membership (valid/invalid) for SIMS total score, affective (AF) subscore, or low intelligence (LI) subscore to a separate valid or invalid group membership based on MMPI-2-RF (VRIN-r and TRIN-r), WAIS-IV Reliable Digit Span, and WMT (IR, DR, and CONS) validity cutoff scores (74% failed >2 measures).

Results

Sample was predominately male (91.6%) and Caucasian (53.8%). Mean age was 35.1 years; mean education was 11.36 years. For SIMS total, 36% failed the SIMS but passed all other validity measures [χ 2(1) = 21.668; p < 0.001; V = 0.427] for a 64% concordance rate for overall valid performance. Individuals with valid scores on the SIMS AF subscale were likely (66%) to have valid performance on all other validity measures [χ 2(1) = 12.418; p < 0.001; V = 0.323]. Individuals with valid scores on the SIMS LI subscale were essentially at chance (52%) to have performed validly overall [χ 2(1) = 9.406; p = 0.002; V = 0.0.281].

Conclusions

In this forensic criminal sample, a third of individuals failed the SIMS total score and AF subscale while having credible performance otherwise. Approximately half failed the LI subscale while passing other validity measures. Results suggest that SIMS performance is not strongly related to SVT measures that focuses on response consistency or PVT performance; there is still significant classification overlap. However, high base rate of PVT/SVT failure in this sample may limit generalizability.

This content is only available as a PDF.
This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://dbpia.nl.go.kr/pages/standard-publication-reuse-rights)
You do not currently have access to this article.