Detection of feigned cognitive dysfunction using special malinger tests: a simulation study in naïve and coached malingerers.

The aim of the present study was to compare the accuracy of the Amsterdam Short Term Memory (ASTM) test with that of the Structured Inventory of the Malingered Symptomatology (SIMS) in detecting feigning of cognitive dysfunction in naïve and coached participants. Ninety undergraduate students were administered the ASTM and the SIMS and asked to respond honestly (controls; n = 30), or instructed to malinger cognitive dysfunction due to head injury. Before the both instruments were administered, naïve malingerers received no further information (n = 30), whereas coached malingerers were given some information about brain injury and a warning not to exaggerate symptoms (n = 30). Both tests correctly classified 90% of the naïve malingerers. The ASTM detected 70% of the coached malingerers, whereas the SIMS continued to detect 90% of them. The findings suggest that coaching undermines the diagnostic accuracy of the ASTM, but does not seem to influence the accuracy of the SIMS.