Diagnostic efficiency of the Rorschach schizophrenia and depression indices in identifying first-episode schizophrenia and severe depression

We studied the diagnostic efficiency of the Rorschach schizophrenia (SCZI) and depression (DEPI) indices for detecting first-episode schizophrenia and severe depression with and without psychotic features using DSM-IV as a gold standard measure. Twenty-seven patients with first-episode schizophrenia, 13 with bipolar I disorder, 28 with psychotic depression, 29 with non-psychotic depression, and 60 healthy controls were recruited for the study. The SCZI was highly specific with a very low false positive rate. The lowest positive value of 4, however, may yield false positives, especially among manic patients. The DEPI identified severe non-psychotic depression but not psychotic depression, suggesting that these patient groups invoke different perceptual-cognitive processes in formulating and articulating their Rorschach responses. Anyway, both the SCZI and the DEPI based on the psychological organization and functioning that are known to play a clearly formulated role in schizophrenia and depression, respectively, provide a valuable addition for diagnostics characterized by overt symptoms.