Neuropsychologists' ability to predict distorted symptom presentation.

OBJECTIVE: We explored to what extent experienced neuropsychologists can predict distorted symptom presentation of clinically referred hospital outpatients.

METHOD: Using clinical files and interview results, 31 neuropsychologists made predictions as to how 203 patients would perform on two response validity tests. Their predictions were matched against actual passing or failing two such tests, of which one measured overreporting of symptoms and the other underperformance on cognitive tests.

RESULTS: Clinical predictions and test outcomes agreed in 76% of the cases, with Cohen's kappa being .26, 95% confidence interval, CI [.08, .44]. Of the 152 patients for whom neuropsychologists had predicted nondistorted symptom presentations, 14 patients (9.2%) failed both response validity tests. Of the 51 patients for whom neuropsychologists had predicted problematic response validity, 35 patients (68.6%) passed both tests.

CONCLUSIONS: Clinical prediction of distorted symptom presentation is far from perfect. Our findings show that response validity tests have incremental value in that they may correct initial clinical judgment.