nurse staffing, hierarchical models, patient outcomes



  1. Estabrooks, Carole A.
  2. Midodzi, William K.
  3. Cummings, Greta G.
  4. Ricker, Kathryn L.
  5. Giovannetti, Phyllis


Background: Evidence indicates that hospital nursing characteristics such as staffing contribute to patient outcomes. Less attention has been given to other hospital nursing characteristics central to optimal professional practice, namely nurse education and skill mix, continuity of care, and quality of the work environment.


Objective: To assess the relative effects and importance of nurse education and skill mix, continuity of care, and quality of work environment in predicting 30-day mortality after adjusting for institutional factors and individual patients characteristics.


Method: A cross-sectional analysis of outcome data for 18,142 patients discharged from 49 acute care hospitals in Alberta, Canada, for diagnoses of acute myocardial infarction, congestive heart failure, chronic obstructive pulmonary disease, pneumonia, or stroke between April 1, 1998, and March 31, 1999, was done. Mortality data were linked to patient demographic and comorbidity factors, institutional characteristics, and hospital nursing characteristics derived from a survey of all registered nurses working in acute care hospitals.


Results: Using multilevel analysis, it was determined that the log-odds for 30-day mortality varied significantly across hospitals (variance = .044, p < .001). Patient comorbidities and age explained 44.2% of the variance in 30-day mortality. After adjustment for patient comorbidities and demographic factors, and the size, teaching, and urban status of the study hospitals in a fixed-effects model, the odds ratios (95% confidence interval) of the significant hospital nursing characteristics that predict 30-day mortality were as follows: 0.81 (0.68-0.96) for higher nurse education level, 0.83 (0.73-0.96) for richer nurse skill mix, 1.26 (1.09-1.47) for higher proportion of casual or temporary positions, and 0.74 (0.60-0.91) for greater nurse-physician relationships. The institutional and hospital nursing characteristics explained an additional 36.9%.


Discussion: Hospital nursing characteristics are an important consideration in efforts to reduce the risk of 30-day mortality of patients.