A multisite study of nurse staffing and patient occurrences.

Restructuring of nursing care models has led to more "non-professional" caregivers, sometimes called unlicensed assistive personnel (UAPs) who provide more of the basic delegable direct patient care activities in collaboration with RNs. The purpose of this study, wherein data were collected from 39 units in 11 hospitals, was to determine the relationship between different levels of nurse staffing and patient outcomes (adverse occurrences). Using and tracking the same indicators of patient quality outcomes over a significant time period in different institutions with similar patient groups would greatly enhance the usefulness of such data. Among the more surprising findings in this study was the "non-linear" relationship between the proportion of RNs in the staff mix and MAEs. As the proportion of RNs on a unit increased from 50% to 85% "the rate of MAEs declined, but as the RN proportion increased from 85% to 100% the rate of MAEs increased." Further investigations are needed to explain this finding.