The Computerized Psychiatric Severity Index as a predictor of inpatient length of stay for psychoses.

The Computerized Psychiatric Severity Index (CPSI), developed by Susan D. Horn and colleagues at The Johns Hopkins University School of Hygiene and Public Health, was used to study the severity of mental illness of 304 patients with discharge diagnosis of schizophrenia or affective disorder, and no secondary psychiatric diagnoses (DRG 430). The CPSI explained 13.7% of the variation in length of stay for these patients (14.31% of the variation in length of stay for affective disorders and 10.04% for the schizophrenia). Length of stay was an appropriate measure of the dependent variable resource use since it correlated 0.96 with total charges.