Table 7Calculated relative risk of hospital-related mortality corresponding to increased RN staffing (results from individual studies)

Study, Analytic UnitRR95% CIData, Definition of RN RatioUnitsPatientsDiagnosis
Mark, 2004181.020.9; 1.1Administrative, RN FTE/1,000 patient daysCombinedCombinedCombined
Mark, 2005191.0050.98;1.03Administrative, RN FTE/1,000 patient daysCombinedCombinedCombined
Robertson, 1999110.970.957; 0.98Administrative, RN FTE/patient dayCombinedMedicalChronic obstructive pulmonary disease
Silber, 2000120.93*p <0.05Administrative, RN FTE/patient daySurgicalSurgicalCombined
Elting, 2005200.61*p <0.05Administrative, RN FTE/patient daySurgicalSurgicalBladder carcinoma (ICD-9 codes 188.0 – 188.9 and 236.7) after total cystectomy
Aiken, 1999100.280.2; 0.5Medical records, RN FTE/patient dayCombinedMedicalAIDS
Aiken, 2002150.580.4; 0.8Administrative, RN FTE/patient dayCombinedSurgicalGeneral surgical, orthopedic, or vascular operation
Aiken. 2003160.890.848; 0.934Administrative, RN FTE/patient dayICUSurgicalGeneral surgical, orthopedic, vascular operation
Person, 2004170.940.9; 1Administrative, RN FTE/patient dayCombinedMedicalAcute myocardial infarction
Pronovost, 199990.02*p <0.05Administrative, patients/RN/shiftICUMedicalAbdominal aortic surgery
Amaravadi, 2000130.39*NSAdministrative, patients/RN/shiftICUSurgicalEsophageal resection
Dimick, 2001146.5*NSAdministrative, patients/RN/shiftICUSurgicalHepatic resection
Halm, 2005211.02*NSAdministrative, patients/RN/shiftSurgicalSurgicalGeneral, orthopedic, and vascular surgery
Hospital unit
Shortell, 199481.13*NSAdministrative, RN FTE/patient dayICUMedicalCombined

95% CI were not reported, significance reported by authors

From: 3, Results

Cover of Nurse Staffing and Quality of Patient Care
Nurse Staffing and Quality of Patient Care.
Evidence Reports/Technology Assessments, No. 151.
Kane RL, Shamliyan T, Mueller C, et al.

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