A - 186 Performance Characteristics of the Structured Inventory of Malingered Symptomatology in a Diverse Community Sample of Social Security Disability Applicants.

Abstract

Analyze performance characteristics of the Structured Inventory of Malingered Symptomatology (SIMS) in a diverse community sample of SSDI applicants. 532 adult SSDI applicants providing research consent were administered the SIMS in conjunction with standard psychodiagnostic, intellectual, and neuropsychological assessments performed in a private practice setting. A broad range of ages and referring diagnoses are represented. Mean age was 42years (SD = 13), with 56% female and 44% male. Based on the nature of the examination, WAIS (n = 47), WMS (n = 60), and Trail Making Test (n = 50) data were obtained, along with performance validity tests (PVTs) including Reliable Digit Span (n = 182), Dot Counting Test (n = 18), and Test of Memory Malingering (n = 70). No meaningful age or gender differences emerged across SIMS scores. The mean SIMS Total Score within this population is 22.9 (SD = 10.1). This compares to a suggested manual cutting score of 14-16 for detection of likely noncredible symptom reporting. 69% of this population produced SIMS Total Scores at or above 16, with 45% of the sample scoring 21 or above. Established studies indicate a roughly 46% base rate of symptom invalidity in SSDI applicants. Standard SIMS cutoff scores when used with this population are likely to overestimate invalidity. Upward adjustment to 21 may be indicated for the SIMS Total Score when attempting to capture a portion of the SSDI population more likely to demonstrate symptom invalidity. Individual subscale performances and correlations with concurrently administered Wechsler scales and PVTs are reported, along with data limitations and additional areas of suggested research.