Red flags in the clinical interview may forecast invalid neuropsychological testing

Evaluating assessment validity is expected in neuropsychological evaluation, particularly in cases with identified secondary gain, where malingering or somatization may be present. Assessed with standalone measures and embedded indices, all within the testing portion of the examination, research on validity of self-report in the clinical interview is limited. Based on experience with litigation-involved examinees recovering from mild traumatic brain injury (mTBI), it was hypothesized that inconsistently reported date of injury (DOI) and/or loss of consciousness (LOC) might predict invalid performance on neurocognitive testing.

This archival study examined cases of litigation-involved mTBI patients seen at an outpatient neuropsychological practice in Philadelphia, PA. Coded data included demographic variables, performance validity measures, and consistency between self-report and medicolegal records.

A significant relationship was found between the consistency of examinees' self-report with records and their scores on performance validity testing, X² (1, N = 84) = 24.18, p < .01, Φ = .49. Post hoc testing revealed significant between-group differences in three of four comparisons, with medium to large effect sizes. A final post hoc analysis found significance between the number of performance validity tests (PVTs) failed and the extent to which an examinee incorrectly reported DOI r(83) = .49, p < .01. Using inconsistently reported LOC and/or DOI to predict an examinee's performance as invalid had a 75% sensitivity and a 75% specificity.

Examinees whose reported DOI or LOC differs from records may be more likely to fail one or more PVTs, suggesting possible symptom exaggeration and/or under performance on cognitive testing.s.