Longitudinal Analyses of Nurse Staffing and Patient Outcomes

BACKGROUND: Numerous studies have examined cross-sectional data to determine the relationships between nurse staffing and patient outcomes. Questions have been raised about some of the studies now in the literature regarding the use of the hospital as the unit of analysis and the cross-sectional design of the studies. Additionally, there is a concern that the primary outcomes being studied are negative. OBJECTIVE: Objectives of this study are to (1) compare the relationships between nurse staffing and positive patient outcomes for 3 adult medical-surgical nursing units in one university teaching hospital across 4 years (16 fiscal quarters); and (2) explore the use of 2 new failure-to-rescue (FTR) rates as outcomes, specifically FTR from medication errors and FTR from decubitus ulcers. DESIGN: This study uses secondary analyses of data viewed retrospectively with a longitudinal repeated-measures design to estimate the relationships between nurse staffing and the outcomes of interest. RESULTS: Accounting for total dollars and case mix, all patient satisfaction measures increased as total hours of care per patient day increased, and as the skill mix became richer (more RN hours/total hours) there was a higher satisfaction with pain management and physical care requests. There was an increase in FTR from medication error as the non-RN (Other) hours of care per patient day increased and there was an increase in FTR from decubitus ulcers as patient severity increased. CONCLUSION: The overall conclusion is that it will likely be necessary to vary staffing hours and staffing mix depending on which positive patient outcome or outcomes you wish to achieve.