Performance validity tests in nonlitigant patients with functional motor disorder.

Area of Science:

• Neuropsychology
• Neurology
• Psychological Assessment

Background:

• Performance validity tests (PVTs) are crucial in neuropsychological assessments to ensure evaluation accuracy.
• Data regarding performance validity in functional motor disorder (FMD) is limited and inconsistent.
• This study addresses the need for clarity on PVT performance in non-litigant FMD patients.

Purpose of the Study:

• To determine the failure rates of three PVTs in non-litigant, non-compensation-seeking FMD patients.
• To compare FMD patients' PVT performance against healthy controls and healthy simulators.
• To assess the clinical utility of PVTs for FMD evaluations.

Main Methods:

• Enrolled 29 FMD patients, 29 healthy controls, and 29 healthy simulators.
• Administered three PVTs: Coin in the Hand Test (CIH), Rey 15-Item Test (REY), and Finger Tapping Test (FTT).
• Analyzed failure rates and compared performance across groups.

Main Results:

• FMD patients exhibited low failure rates: 7% on CIH, 10% on REY, and 15% on FTT.
• FMD patients' performance was statistically similar to healthy controls.
• FMD patients' performance significantly differed from healthy simulators (p < 0.001).

Conclusions:

• PVT performance in FMD patients ranged from 7% to 15% failure.
• The findings support the validity of PVT use in FMD assessments.
• A simple battery of three PVTs is proposed for routine clinical use in FMD evaluations.