Police, ambulance and mental-health clinician early response (PACER) models in Australia and New Zealand: a narrative review of emergency department impacts and consumer and service provider experiences

Abstract

AimTo examine PACER models in Australia and New Zealand in relation to association with emergency department (ED) presentations, provider, and consumer experiences and assess acceptability and inform service development.BackgroundMental-health crises account for an increasing proportion of ED presentations and frequently involve police and ambulance services. Traditional ED-centred pathways may contribute to negative experiences and fragmented care. PACER models embed a mental-health clinician alongside police and paramedics to enable on-scene assessment, de-escalation, and triage to community-based pathways.MethodA narrative literature review guided by the PICO framework was undertaken. Electronic databases and grey literature were searched for Australasian sources published between 2007 and 2025. Nine empirical studies and 12 contextual or policy-relevant sources were included and synthesised using inductive thematic analysis.ResultsThree domains were identified: (1) impact on ED presentations, (2) provider perspectives, and (3) consumer experiences. PACER models were associated with increased on-scene resolution, enhanced collaborative decision-making, and more person-centred crisis responses. Evidence was descriptive.ConclusionPACER models represent a promising, integrated approach to mental-health crisis response, associated with reduced reliance on emergency departments and more acceptable, collaborative care. Future evaluations are required to examine effectiveness, optimise consumer and provider experiences, and determine system-level impact.