Nurse Staffing in Psychiatric Inpatient Care: A Multicentre Study Using Routine Patient and Structural Data.

Data from 107 psychiatric inpatient units in 13 hospitals (25,294 patient cases) showed wide variation in unit structures and patient mental health status but relatively little variation in staffing patterns.

The median number of beds was 21, and the typical early shift included 2 registered nurses.

Regression analyses indicated that higher Health of the Nation Outcome Scales total scores and several single items were significantly associated with increased RN staffing, with the total score showing the strongest effect.

Comparing predicted with reported staffing, smaller units tended to fall below and larger units above their predicted levels.