Nurse staffing and patient safety: current knowledge and implications for action.

Over the past year, published research has drawn increased attention to issues of hospital nurse staffing and adverse patient outcomes. Among the published articles that have appeared are those by Aiken et al. [1], Kovner et al. [2], and Needleman et al. [3]. The article by Aiken et al. focused on post-surgical mortality, and received substantial attention because of its conclusion that, controlling for patient and hospital characteristics, the addition of one patient to a registered nurse's workload was associated with a 7% increase in mortality.