: Factors associated with emergency department service outcomes for people with a mental health problem brought in by police: a retrospective cohort study.

Objective This study aimed to identify factors associated with an emergency department (ED) length of stay ≥4 hours (h) and hospital admission for people with a mental health problem brought in by police. Methods We undertook a retrospective, observational cohort study of state-wide adult ED mental health presentations brought in by police from 1 January 2012 to 31 December 2017. We used multivariable logistic regression to determine factors associated with an ED length of stay ≥4 h and hospital admission. Results In total, 9325 ED presentations with a mental health problem brought in by police to Queensland EDs were included. Factors most strongly associated with an ED length of stay ≥4 h included an Australasian Triage Score (ATS) of 1, an age of 85 years or older, night shift arrival and subsequent hospital admission. For hospital admission, an ATS of 1, an age of 85 years or older and an ED length of stay ≥4 h were the strongest factors. Conclusion Findings indicate opportunities for targeted mental health models of care to better support people brought in by police to an ED. Such models should involve ED, pre-hospital providers (police and ambulance) and mental health services to support early intervention and potentially reduce the likelihood of a long ED length of stay and subsequent hospital admission.