Types or modes of malingering? A confirmatory factor analysis of performance and symptom validity tests.

Recently, the dichotomy between performance validity tests (PVT) and symptom validity tests (SVT) has been suggested to differentiate between invalid performance and invalid self-report, respectively. PVTs are typically used to identify malingered cognitive impairment, while SVTs identify malingered psychological or somatic symptoms. It is assumed that people can malinger different types of problems, but the impact of modes of reporting invalidly has been largely unexplored. A mixed neurological sample (n = 130) was tested with the Test of Memory Malingering, the Forced Recognition part of the California Verbal Learning Test, and the self-report Structured Inventory of Malingered Symptoms (SIMS). Confirmatory factor analyses testing both method- and content-based factor models found best fit for the method-based division. Regression analyses of other self-rating and performance-based tests provided further support for the importance of type of methods used to collect information. While acknowledging the types of symptoms malingered, the clinician is advised also to consider how information is gathered by using both PVTs and SVTs. SIMS is a good candidate for a stand-alone SVT, although the utility of the Low Intelligence subscale is questionable as a validity measure.