Leveraging Clinical Expertise as a Feature - not an Outcome - of Predictive Models: Evaluation of an Early Warning System Use Case

Identifying patients at risk of deterioration in the hospital and intervening more quickly to prevent adverse events is a top patient safety priority. Early warning scores (EWS) identify at risk patients, but there is much opportunity for improvement particularly related to increasing lead time - the time from an alert trigger to adverse event (e.g., cardiac arrest, death). Our team develops healthcare process models of clinical concern (HPM-CC) and in this work has identified documentation signals that are proxies of nurses concern and can be used to predict patient risk earlier than current EWS systems that rely only on physiological data. We compared the performance of a validated EWS - the MEWS - to our novel model (MEWS-CC) comprised of MEWS criteria plus 3 proxy variables of nursing concern. MEWS-CC performed similarly to MEWS, with the added benefit of increased the time from EWS trigger to event by 5-26 hours.