Evaluation of the appropriateness of multiple symptom validity indices in psychotic and non-psychotic psychiatric populations.

Although it is recognized that significant cognitive deficits are inherent in many psychiatric disorders, there is minimal research on whether the deficits can cause a failing score on symptom validity tests (SVTs). The performances of 104 and 178 patients with psychotic disorders and non-psychotic psychiatric disorders, respectively, on seven SVTs were examined. Analyses indicate that most of these SVTs have specificity rates of 90% or better for both clinical groups. Further, only 7% of patients in the psychotic group and 5% of patients in the non-psychotic psychiatric group produced false-positive classifications based on malingering criteria similar to those suggested by Slick et al. (i.e., failure of two or more SVTs or failure of one SVT at statistically significantly worse than chance rates). Consequently this research indicates that psychiatric disorders typically do not adversely affect SVT performance.