Four-quadrant analysis of universal health coverage progress in the Western Pacific region: facilitators, barriers, and trajectories to 2030

BACKGROUND: Universal health coverage (UHC) progress in the Western Pacific Region (WPR) varies across countries and between service coverage (SDG 3.8.1) and financial hardship (SDG 3.8.2). OBJECTIVES: To characterize patterns and trajectories of UHC progress in the WPR, identify associated health-system and socioeconomic factors, and project progress to 2030. METHODS: This convergent mixed-methods study used data from the WHO, World Bank, and UN. Countries were classified according to a four-quadrant typology, with 2022 global estimates of SDG 3.8.1 and 3.8.2 serving as reference benchmarks. Fixed-effects panel models were employed to examine associations of SDG 3.8.1 with key covariates. Peer-reviewed, policy, and grey literature were analyzed using the READ approach and thematic framework analysis, while Bayesian models were used to project UHC progress to 2030. RESULTS: From 2000 to 2022, SDG 3.8.1 in the WPR rose from 63 to 81, while SDG 3.8.2 fell from 39.6% to 27.0%. Twelve countries were classified as low SDG 3.8.1/low SDG 3.8.2, five as high/low, three as low/high, and China alone as high/high. More favorable patterns were associated with stronger financing, primary health care orientation, workforce capacity, and governance, whereas less favorable patterns were linked to fragmented financing, workforce shortages, remoteness, climate vulnerability, and population ageing. SDG 3.8.1 was positively associated with education and urbanization and showed an inverted U-shaped relationship with GDP per capita. By 2030, SDG 3.8.1 and SDG 3.8.2 are projected to reach 85.6% and 22.2%, respectively. CONCLUSION: Accelerating progress will require context-specific reforms tailored to individual countries.