Use of the SIRS in compensation cases: an examination of its validity and generalizability

Abstract

The Structured Interview of Reported Symptoms (SIRS; Rogers et al., Structured interview of reported symptoms (SIRS) and professional manual, 1992) is a well-validated psychological measure for the assessment of feigned mental disorders (FMD) in clinical, forensic, and correctional settings. Comparatively little work has evaluated its usefulness in compensation and disability contexts. The present study examined SIRS data from 569 individuals undergoing forensic neuropsychiatric examinations for the purposes of workers' compensation, personal injury, or disability proceedings. Using bootstrapping comparisons, three primary groups were identified: FMD, feigned cognitive impairment (FCI), genuine-both (GEN-Both) that encompasses both genuine disorders (GEN-D) and genuine-cognitive presentation (GEN-C). Consistent with the SIRS main objective, very large effect sizes (M Cohen's d = 1.94) were observed between FMD and GEN-Both groups. Although not intended for this purpose, moderate to large effect sizes (M d = 1.13) were found between FCI and GEN-Both groups. An important consideration is whether SIRS results are unduly affected by common diagnoses or clinical conditions. Systematic comparisons were performed based on common disorders (major depressive disorder, PTSD, and other anxiety disorders), presence of a cognitive disorder (dementia, amnestic disorder, or cognitive disorder NOS), or intellectual deficits (FSIQ < 80). Generally, the magnitude of differences on the SIRS primary scales was small and nonsignificant, providing evidence of the SIRS generalizability across these diagnostic categories. Finally, the usefulness of the SIRS improbable failure-revised (IF-R) scale was tested as a FCI screen. Although it has potential in ruling out genuine cases, the IF-R should not be used as a feigning screen.