Medical Symptom Validity Test Performance Following Moderate-Severe Traumatic Brain Injury: Expectations Based on Orientation Log Classification.

OBJECTIVE

This study examined performance on the Medical Symptom Validity test (MSVT) during acute rehabilitation for moderate-severe traumatic brain injury (TBI) stratified by Orientation Log (O-Log) scores.

METHOD

Participants were 77 prospectively enrolled persons who sustained moderate-severe TBI and were acutely hospitalized secondary to the cognitive, medical and physical sequelae of their TBI. Participants were administered neuropsychological metrics, the O-Log and the MSVT a mean of 44 days post injury.

RESULTS

Significantly lower neurocognitive test scores were observed among participants who remained in post-traumatic amnesia (O-Log scores ranging from 20 to 24) versus those who were oriented (O-Log scores ranging from 25 to 30). MSVT performance was lower among participants who remained in post-traumatic amnesia. When participants O-Log scores were unimpaired (30), performance on the MSVT was also unimpaired on immediate recognition (IR) and delayed recognition (DR). A small percentage of participants performed below MSVT interpretive expectations on CNS. As O-Log scores decreased, MSVT performance also declined on some, but not all MSVT metrics. The sample as a whole performed at or above expectations on MSVT criterion B2 (IR) = 96.6%; (DR) = 94.8%; consistency (CNS) = 92.9%; paired associate (PA) = 86.4% and delayed free recall (FR) = 46.8%.

CONCLUSIONS

MSVT performance stratified by O-Log scores provides basal expectation levels for persons with acute, moderate-severe impairment in cognitive skills secondary to TBI. Our data demonstrate that persons with significant neurocognitive impairment who are oriented generally perform at or above MSVT interpretive guidelines.