Association Between Nurse Staffing Coverage and Patient Outcomes in a Context of Prepandemic Structural Understaffing: A Patient‐Unit‐Level Analysis
Maria‐Eulàlia Juvé‐Udina, Jordi Adamuz, Maribel González‐Samartino, Marta Tàpia‐Pérez, Emilio Jiménez‐Martínez, Carme Berbís‐Morelló, Oliver Polushkina-Merchanskaya, Adelaida Zabalegui, María‐Magdalena López‐Jiménez
Abstract
Objective: To evaluate the association between nurse staffing coverage and patient outcomes in a context of structural understaffing. Design: This is a population‐based, cross‐sectional, multicenter study, including patient and staffing data from eight public hospitals from Catalonia, Spain. Participants: A total of 183,085 adult in‐patients admitted to hospital wards and step‐down units during 2016 and 2017. Outcomes: In‐hospital mortality, 30‐day hospital readmission, and three cluster nurse‐sensitive adverse events: healthcare‐acquired infections, failure to maintain, and avoidable critical complications. The study factor is safe nursing staffing equivalent to nurse staffing coverage > 90%. Results: Average patient acuity was equivalent to 4.5 required nursing hours per patient day. The mean available nursing hours per patient day was 2.6. The average nurse staffing coverage reached 65.5%. Overall, 1.9% of patients died during hospitalization, 5% were readmitted within 30 days, and 15.9% experienced one or more adverse events. Statistically significant differences were identified for all patient outcomes when comparing patients safely covered (nurse staffing coverage > 90%) and under‐covered (nurse staffing coverage < 90%). Increasing nurse staffing coverage to a safe level (> 90%) is associated with a reduction of the risk of death (RR: 0.41, 95% CI: 0.37–0.45), a decrease in the risk of hospital readmission (RR: 0.93, 95% CI: 0.89–0.97), and a reduction of nurse‐sensitive adverse events (RR: 0.67, 95% CI: 0.66–0.69). Conclusion: Safe nurse staffing coverage acts as a protective factor for detrimental patient outcomes, significantly reducing the risk of in‐hospital mortality, 30‐day hospital readmission, healthcare‐associated infections, failure to maintain, and avoidable critical complications. Further policy efforts are needed to guarantee a safe registered nurse staffing coverage.