Nurse staffing, nursing intensity, staff mix, and direct nursing care costs across Massachusetts hospitals

Objective: This study describes the distribution of patient-to-registered nurse (RN) ratios, RN intensity of care, total staff intensity of care, RN to total staff skill mix percent, and RN costs per patient day in 65 acute community hospitals and 9 academic medical centers in Massachusetts. Methods: We conducted a retrospective secondary analysis of the Patients First database published by the Massachusetts Hospital Association for planned nurse staffing in 601 inpatient nursing units in the state for 2005 using a multivariate linear statistical model controlling for hospital type and unit type. Nursing unit types were identified as adult and pediatric medical/surgical, step down, critical care, neonatal level II, and neonatal level III/IV nurseries. Results: Medical centers had significantly higher case-mix index (1.72 vs 1.20, P < .001), longer lengths of stay (5.18 vs 4.19, P < .001), more beds (574 vs 147, P < .001), discharges (31,597 vs 7,248, P < .001), and patient days (161,440 vs 31,020, P < .001) compared with to community hospitals. Medical centers had significantly lower patient-to-RN ratios (3.22 vs 4.64, P < .001), higher nursing intensity and total nursing staff intensity (9.62 vs 7.43/11.75 vs 9.87, both P < .001), higher percent of RN to all staff mix (79% vs 71%, P < .001), and higher RN costs per patient day ($385 vs $297, P < .001) compared with to community hospitals. There were significant differences in adult med/surg units between community hospitals and medical centers for patient-to-RN staffing ratios (5.25 vs 4.08), nursing intensity (5.1 vs 6.2 hours daily), skill mix (67% vs 73% RN), and RN costs per patient day ($203 vs $248, all P < .001). There were no significant differences between the adult step-down units. Conclusion: The significant differences between community hospitals and medical centers, unit type, as well as the high degree of variability in patient-to-RN ratios, nursing intensity, skill mix, and RN costs per patient day suggest that nursing resource expenditure at Massachusetts hospitals is complex and affected by case mix, unit size, and complexity of care.