Distinguishing between Neuropsychological Malingering and Exaggerated Psychiatric Symptoms in a Neuropsychological Setting

Abstract

It is unclear whether symptom validity test (SVT) failure in neuropsychological and psychiatric domains overlaps. Records of 105 patients referred for neuropsychological evaluation, who completed the Test of Memory Malingering (TOMM), Reliable Digit Span (RDS), and Millon Clinical Multiaxial Inventory–III (MCMI–III), were examined. TOMM and RDS scores were uncorrelated with MCMI–III symptom validity indices and factor analysis revealed two distinct factors for neuropsychological and psychiatric SVTs. Only 3.5% of the sample failed SVTs in both domains, 22.6% solely failed the neuropsychological SVT, and 6.1% solely failed the psychiatric SVT. The results support a dissociation between neuropsychological malingering and exaggeration of psychiatric symptoms in a neuropsychological setting.

Keywords:

• Malingering
• Neuropsychology
• Personality
• Symptom validity

ACKNOWLEDGMENTS

The authors acknowledge Danielle Raines for her assistance with data entry. The first author acknowledges fellowship support from the Drexel University College of Arts & Sciences and Natural Sciences & Engineering Research Council of Canada.

Notes

^a TOMM = Test of Memory Malingering.

^b n = 32.

^c MCMI = Millon Clinical Multiaxial Inventory–Base Rate scores.

^a TOMM = Test of Memory Malingering.

^b n = 77.

^c MCMI = Millon Clinical Multiaxial Inventory–Base Rate scores.

^a RDS = Reliable Digit Span (n = 77).

*Two-tailed p < .01.

The intercorrelation of the factors was r = –.13 (p = .25).

Overlap of participants passing or failing the TOMM and exaggerating or not exaggerating psychiatric symptoms on the MCMI–III (Scale Z cutoff BR ≥ 85).

TOMM + = valid TOMM; TOMM– = failed TOMM; MCMI + = Scale Z BR < 85; MCMI − = Scale Z BR ≥ 85.

TOMM + = valid TOMM; TOMM − = failed TOMM; MCMI + = Scale Z BR < 85; MCMI − = Scale Z BR ≥ 85.

*Significantly different from one another (p < .01).