Cross-validating factors associated with discharges against medical advice.

Between six percent and 35% of psychiatric patients discharge themselves from hospital against medical advice (AMA). The discharges may prevent patients from deriving the full benefit of hospitalization and may result in rapid rehospitalization. We examined sociodemographic and clinical characteristics of 195 irregular discharges from a 237 bed psychiatric hospital over a five year period and found that AMA discharges increased over the study period to a peak of 25% in 1986. There was a strong negative correlation between AMA discharge rates and the willingness of physicians to commit patients involuntarily. Multiple discriminant analysis revealed a set of nine variables that accurately classified 78% of cases into regular or irregular discharge categories. Further analysis revealed that there are two distinct subgroups of patients who discharge themselves AMA: those who repeatedly left the hospital AMA in a regular "revolving back door" pattern and those who left AMA only once. The repeat group exceeded the one-time group in terms of prior admissions, appearances before review boards, and percentage of Natives. The repeat group also spent twice as long in hospital, and 27% were readmitted within one-week of the index AMA discharge. Less than three percent of the one-time AMA group was readmitted within a week. These results were cross-validated on a new sample of irregular discharges and matched controls.