Patient outcomes associated with nurse staffing*
| Author | Country | Design | No of EDs | Comparisons | Outcome | Key results | Patients seen (census) | Internal validity | External validity |
|---|---|---|---|---|---|---|---|---|---|
| Brown et al11 | USA | Retrospective Observational | 1 | Actual compared with scheduled RN staffing hours | Left without being seen | RNs staffing predictor of a higher number of patients leaving without being seen | 50 000 | − | − |
| Chan et al14 | USA | Prospective Observational | 2 | Mandated nurse-patient ratios compared with out-of-ratio care | Time to antibiotic administration | Shorter time to antibiotic administration if nurse staff in ratio | 61 000 | + | − |
| Chan et al10 | USA | Prospective Observational | 2 | Mandated nurse-patient ratios compared with out-of-ratio care | Waiting time Emergency department care time | Longer wait times when the ED overall was out-of-ratio. Longer ED care time for patients whose nurse was out-of-ratio. | 59 733 | + | − |
| Daniel15 | Can | Retrospective Observational | 107 | Nurse-patient ratios | Patient satisfaction | Increase in overall patient satisfaction associated with nurse staff skill mix. Per cent of full-time nursing worked hours negatively associated with overall patient satisfaction. Physician and nurse courtesy highly associated with patient satisfaction. | 182 022 | + | + |
| Greci et al13 | USA | Cross-sectional | 1 | Staff workload when the ED was crowded and not crowded | Left without being seen Ambulance diversion | RN:patient ratio significantly associated with patient leaving without being seen No association with ambulance diversion RN:patient ratio significantly associated with perception of crowding | 30 000 | − | − |
| Hoxhaj et al12 | USA | Retrospective Observational | 1 | Nurse staffing levels | Left without being treated | No. of nursing vacancies (FTE) strongly correlated with percentage of patients who left without being treated Total monthly nursing hours to monthly ED census ratio strongly correlated with percentage of patients who left without being treated | 92 000 | − | − |
| Rathlev et al16 | USA | Time series | 1 | Number of ED nurses on duty Hospital occupancy Number of patients admitted to the hospital Number of patients admitted from ED to ICU Number of ED resuscitation cases | Length of stay (LOS) | Numbers of nurses, ED discharges on previous shift, resuscitation cases, and elective surgical admissions not associated with LOS on any shift. LOS reduced per additional nurse (average staff level unclear) | 91 643 | + | − |
| Schull et al17 | Can | Retrospective Observational | 1 | Number of patients boarded in the ED Number of ED nurse hours worked per shift Number of emergency physicians per shift | Ambulance diversion | Number of admitted patients boarded in the ED predictor of increased ambulance diversionED nurse hours not associated with crowding | 37 999 | − | − |
| Weichenthal and Hendey9 | USA | Before and after | 1 | Nurse-patient ratios | Waiting times, Left without being seen, Medication errorsTime to aspirin administrationTime to antibiotic administration | After the introduction of nursing ratios ▸ wait times increased significantly ▸ Percentage of patients who left without being seen decreased ▸ No significant change in reported medication errors after the implementation of nursing ratios ▸ No significant change in the rate of aspirin administration. ▸ For patients with pneumonia, decrease time from written order to administration of antibiotics | 59 163 (before) 55 976 (after) | − | − |
*Internal/external validity (+, −). The summary bias assessment was completed from a detailed evaluation that considered risk adjustment, data completion and sampling strategy across data sources, outcome types and levels. Ratings were summarised to give a + for some of the assessment criteria fulfilled and conclusions unlikely to change or − for few criteria fulfilled and conclusions likely to change. During quality assessment, no studies were rated ++ indicating that the method was likely to minimise bias or with conclusions unlikely to change.
ED, emergency department.