Phenomenology of organic and functional psychoses and the overlap between them.

The Present State Examination was conducted upon 328 recently admitted psychotic patients, of whom 23 were later found to have underlying organic illness. The phenomenology in these 23 was compared with that of 92 matching controls drawn from the parent sample who conformed to DSM-III criteria for schizophrenia, mania and depression. Few significant differences were present and there was considerable overlap between the diagnostic groups.