Evaluation of clinical diagnostic criteria for psychogenic movement disorders.
Previous studies showed that there are certain features suggestive of a psychogenic disorder, and Fahn and Williams proposed criteria for psychogenic movement disorders. Data on the sensitivity and specificity of these criteria are lacking. We expanded on the Fahn and Williams criteria to create a new set of diagnostic criteria. We retrospectively reviewed 79 patients in a movement disorders specialty clinic. We applied the proposed diagnostic criteria to both cases and controls and analyzed sensitivity and specificity. The diagnostic criteria correctly identified "clinically probable" (or better) psychogenic movement disorders with a sensitivity of 83% and specificity of 100%. For "clinically possible" or greater, sensitivity was 97% and specificity was 96%. In addition, a significantly higher proportion of patients with psychogenic disease were female and reported either a family history of neurological disease or other exposure to neurological disease (P = 0.001 and 0.01, respectively). The diagnostic criteria are simple to apply and have high sensitivity and specificity for psychogenic movement disorders. Also, we report a correlation between previous exposure to a disease model and psychogenic disease.