Cho et al.

(2003) [16]

can’t tell



Examine the effects of nurse staffing on adverse events, morbidity, mortality and medical costs

Existing databases from 232 acute care hospitals and 124,204 patients in 20 surgical diagnosis-related groups.

857 patients with hemorrhagic and ischemic stroke who were admitted to ICUs of 185 Korean hospitals

An increase of one hour worked by registered nurses per patient per day was associated with an 8.9% decrease in the odds of pneumonia.

Hospitals with higher ICU staffing were more likely to fully provide basic care. Better staffing were associated with lower in-hospital and 30-day mortality. 30-day mortality had a more distinct decrease with lower staffing rates

Direct consequence: Patient harm

Cho & Yun

(2009) [34]

Cross-sectional design including a survey



To examine differences in provision of basic nursing care and in-hospital and 30-day mortality by nurse staffing of ICUs and general wards among acute stroke patients

ICUs of 185 Korean hospitals

Better staffing was associated with lower in-hospital and 30-day mortality. 30-day mortality had a more distinct decrease with lower staffing rates.

Direct consequences: Mortality

Cimotti et al.

(2006) [35]

Prospective cohort study



To examine the association between registered nurse staffing and healthcare associated bloodstream infections in infants in neonatal intensive care units.

2675 infants admitted to the NICUs for more than 48 hours and all registered nurse who worked in the same NICUs during the study

A greater number of hours of care provided by RNs in NICU 2 were associated with decreased risk of bloodstream infections.

Number of hours of care provided by RNs in NICU 1 was not associated with bloodstream infections.

Direct consequences: Patient harm

de Cordova et al. (2014) [37]

Longitudinal study



Examine the association between night nurse staffing and work force characteristics and length of stay (LOS)

Monthly observations of administrative data from 138 acute care hospitals (N = 8243)

Higher night staffing and higher skill mix were associated with reduced LOS

Direct consequences: Patient harm

Daud-Gallotti et al.

(2012) [36]

Prospective cohort study



Evaluate the role of nursing workload in the occurrence of HAI in medical intensive care units.

195 ICU-Patients

22% developed HAI (healthcare-associated infection). Average NAS (Nursing activity score) and average proportion of non-compliance with NPC (Non-compliance to the nurse’s patient-care plans) were significantly higher in HAI patients.

Only excessive nursing workload and severity of the patient’s clinical condition remained as risk factors to HAI.

Direct consequences: Patient harm

Duffield et al.

(2011) [17]


Retrospective study combined with a cross-sectional study



Examine the relationship of nurse staffing and workload, in the context of the work environment, to patient outcomes.

Data from the public hospital system. Five years of data for 80 public hospitals

Increased RN staff were associated with significantly decreased rates of pressure ulcer, pneumonia, and sepsis, GI bleeding, physiological/metabolic derangement, pulmonary failure, sepsis and shock. There were several nursing-tasks left undone or postponed as a consequence of heavy workload.

Direct and indirect consequences: Poor basic care quality and patient harm