Relationship between staffing ratios and effectiveness of inpatient psychiatric units

Objective: Most staffing models designed for adult psychiatric hospitals ar e based on the well-known relationship between high staff-patient ratios an d high effectiveness of treatment units. Staffing ratios likely gain their predictive power by serving as a proxy measure for the amount of attention patients receive from staff. This study directly measured the amount of att ention that patients received from staff to determine whether it could acco unt for the variance in unit effectiveness predicted by staffing ratios and serve as a better predictor of unit effectiveness. Methods: Data from 22 w ards in state or Department of Veterans Affairs mental health institutions, which housed 673 short- and long-stay patients, were analyzed. Only full-t ime direct care staff were included in the calculation of staff-patient rat ios. The amount of attention provided to patients by staff was determined o ver seven days by a highly reliable observational assessment system. The tw o best social-action outcome measures over a six-month period were adjusted for confounding variables to provide residualized indexes of unit effectiv eness. Results: Staff-patient ratios significantly predicted unit effective ness as indexed by residualized community tenure, accounting for 24 percent of the variance. However, staff-patient ratios did not significantly predi ct unit effectiveness as indexed by net gain in discharge rates. Taking int o account the amount of staff attention received by patients significantly improved the prediction of community tenure by 36 percent and the net gain in discharge rates by 66 percent over staffing ratios alone. The amount of staff attention also accounted for the relationship between staffing ratios and community tenure. Conclusions: Staffing decisions should be made on th e basis of more precise information about treatment requirements, not just staffing ratios.