Geographic equity in residential aged care quality: spatial and longitudinal analysis of Australia’s Star Ratings system

OBJECTIVE: This study aimed to examine geographic variation, temporal trajectories, and equity dimensions of quality in Australian residential aged care using the Star Ratings system introduced in late 2022. METHODS: A repeated cross-sectional and longitudinal panel analysis of publicly available administrative data was performed. All 3002 rated residential aged care facilities were observed across 11 quarterly Star Ratings extracts (May 2023 to October 2025), yielding 28,708 facility-quarter records. Spatial clustering was assessed using Global and Local Moran's I. Overall-rating trajectories by provider type were modelled using linear mixed-effects models with facility random intercepts and slopes. Residential aged care quality deserts were defined as regions beyond 50 km from a rated mainstream residential facility. The results are reported as per STROBE guidelines. RESULTS: The mean overall rating improved from 3.38 to 3.87 stars, with improvement decelerating over time (P < 0.001). For-profit facilities rated 0.10 stars lower than not-for-profit (P < 0.001) and were 2.75 times more likely to be persistently low-performing (odds ratio 2.75; 95% CI 1.13-6.70). Overall ratings clustered spatially (Moran's I = 0.24, P < 0.001), with 17 low-rating clusters predominantly in Western Australia and South Australia. Eleven residential aged care quality deserts affected 14,056 people aged 65 and older; desert status is driven by remoteness, with disadvantage showing no independent association after adjustment (P = 0.60). CONCLUSIONS: Star Ratings, best interpreted as a regulatory and consumer signal rather than a validated measure of care quality, have improved substantially over the period observed; a persistent for-profit gap in overall ratings and geographic clustering present opportunities for targeted regulatory scrutiny.