Activity-withdrawal in the differential diagnosis of schizophrenia and mania

Used the Activity-Withdrawal Scale (P. H. Venables, 1957) to blindly rate 30 stringently diagnosed, acutely psychotic manics and schizophrenics. Ratings were made by ward staff. Manics received significantly higher ratings than schizophrenics on the scale, with 9 of the scale's 10 items significantly discriminating the 2 groups. Using a cutoff point from past research, the total scale score correctly classified over 83% of the sample as manic or schizophrenic. A classification of active predicted a Research Diagnostic Criteria diagnosis of mania with 92% accuracy, whereas a classification of withdrawn predicted a diagnosis of schizophrenia in 78% of the cases. (47 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).