Study of emergency department (ED) nursing workload has been largely subsumed under the related but separate phenomenon of ED crowding. Nursing workload is difficult to quantify directly. This observational study explored modeling ED nursing workload indirectly, in real time, from quantitative data available from the patient tracking computer system (PTCS).

METHODS: Data on 2793 patient visits plus departmental statistics were collected during 167 60-minute survey periods (SP) in a 25-bed hospital ED in the United States. The charge nurse assessed a perceived workload score (WLS) according to pre-determined criteria following each SP as a validation measure.

DATA ANALYSIS: Correlations were calculated between the data and WLS, and strongly correlating variables were incorporated into linear regression models that sought to approximate WLS.

RESULTS: A measure of aggregate patient acuity derived from the Emergency Severity Index (ESI) was the strongest predictor of WLS (r = 0.7991). The best-performing model agreed with WLS in 64% of SPs.

CONCLUSIONS: Good agreement between model output and WLS suggests that ED nursing workload can be estimated indirectly in real time using data from a PTCS. Strong correlation between the ESI derivative and WLS further validates ESI and suggests a new application for the ESI score.