A number of factors including previous history of hospitalization, emergent versus voluntary nature of the admission, diagnosis, unplanned discharge, medical comorbidity, and length of time in the hospital can all predict likelihood of readmission after discharge from a psychiatric hospitalization. The READMIT tool is an example of a tool that combines these variables into a single score that can help predict likelihood of readmission.
Vigod et al. READMIT: A Clinical Risk Index to Predict 30-day Readmission After Discharge From Acute Psychiatric Units. J Psychiatr Res 2015 Feb;61:205-13.