Malingering of head injury on neuropsychological instruments, a meta-analytic review

by Sullivan, Lynne Elaine

There is a relatively large body of literature investigating malingering of head injury using neuropsychological instruments (Faust & Ackley, 1998; Nies & Sweet, 1994; Rogers, HarrelI, & Liff, 1993). To date, there has been no consensus in the literature as to which instrument(s) is superior at distinguishing between head injury malingerers and nonmalingerers. Furtherrnore, although a number of reviews have addressed the effectiveness of different strategies for identifying malingering, no meta-analytic studies of the literature have been undertaken to identify which rneasures perform best at detecting rnalingerers. The purpose of this study was, first of al!, to identify such measures. Matingerers were compared both to normal controls and to brain-injured individuals. Second, the effectiveness of instruments from different cognitive domains in identifying malingerers was investigated along with the interaction between type of instrument and type of malingerer (Naïve, Coached, or Suspected malingerers, and Litigants). The moderating influence of study and participant characteristics was also investigated. Results indicated that malingerers could best be distinguished from nonmalingerers by recognition tasks (e-g., the Recognition Memory Test), as well as tests designed specifically to assess malingering (e.g., the Portland Digit Recognition Test). On malingeringtests, the differences between types of rnalingerers were eliminated, but on other neuropsychological instruments, Coached participants performed significantly worse than did other types of malingering participants. Atso on malingering tests, there were no differences among malingering groups when compared to either normal or brain-injured comparison groups. When malingerers were compared to normals on other neuropsychologicai instruments, effect sizes were largef thah when malingefers were compared to brain-injured individuais. Overall, the resultS sU~gest that at least some neuropsychological instruments are valid for distinguishing behnreenmalingerers and non-malingerers.