Abstract
BACKGROUND: The number of calls for ambulances in Australia has been rising faster than population growth, but it is unclear what is driving this demand. This study aims to quantify and compare the drivers of emergency ambulance demand in Victoria, Australia, before and after the COVID-19 pandemic, including demographic and clinical factors. METHODS: We conducted a retrospective cohort study of all emergency ambulance calls in Victoria from January 1, 2016, to December 31, 2023. Using negative binomial segmented time series regression models, adjusted for population growth and seasonality, we estimated trend and level changes across demographic and clinical subgroups. RESULTS: 5,239,378 calls were analysed. Ambulance demand increased annually by 4.3% [95% CI 3.6,5.1] pre-COVID-19, but slowed to 2.7% [95% CI 0.9, 4.5] post-pandemic. Post-COVID-19, there was a decreasing trend in calls among children, rural residents, and patients with lower socioeconomic advantage. The trend in demand also declined for calls related to chest pain, cardiac arrest, and falls. In contrast, there was an increasing trend among older adults and for complaints including headaches, heart problems, and trauma. Psychiatric calls showed continued growth across all periods, despite a level decrease at the end of COVID-19. CONCLUSIONS: Altered patterns of ambulance utilisation were observed in Victoria post-COVID-19. Reduced demand growth post-COVID-19 may reflect a diversion toward urgent care centres and the growing role of telehealth. Ongoing increases in psychiatric demand highlight the need for system-level interventions to manage mental health presentations. Calls for falls increased proportionally with population growth, indicating that falls are not a significant driver of ambulance demand. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12873-026-01548-1.