Firm structure, organisational capacity, and employer health insurance provision in Oman: a cross-sectional mediation study

Employer mandates are a central mechanism for expanding universal health coverage (UHC). In Oman, the Dhamani platform a national digital health-insurance system mandates private-sector coverage under Capital Market Authority Resolution 78/2019. Full national rollout commenced in 2025, creating an urgent need for pre-implementation employer-readiness evidence. To describe formal employer health-insurance provision rates across Omani private-sector firms, to identify firm structural factors independently associated with provision, and to assess whether organisational resource capacity mediates the firm size–provision relationship. Cross-sectional employer survey ( n = 222) conducted prior to full Dhamani enforcement, using stratified purposive sampling by firm size and sector. Multivariable logistic regression (Hosmer–Lemeshow calibration, ROC AUC discrimination, VIF multicollinearity checks, Box–Tidwell linearity test, Firth penalized sensitivity analysis) and bootstrapped mediation analysis (5,000 resamples; bias-corrected 95% CI as primary inferential result) were used. Formal provision was 36.5% overall (95% CI: 30.2–43.1%), ranging from 10.8% among micro-enterprises to 81.0% among large firms (Cramér’s V = 0.573, p < 0.001). Organisational resource capacity was the strongest independent predictor (AOR = 31.51, 95% CI: 11.82–84.01, p < 0.001). The bootstrapped indirect effect of firm size on provision through capacity was 0.413 (bias-corrected 95% CI: 0.189–0.687), representing 30.3% of the total association. Model discrimination was good (ROC AUC = 0.88, 95% CI: 0.83–0.93) and calibration was acceptable (Hosmer–Lemeshow p = 0.45). A post-stratification weighted estimate adjusting for micro-enterprise oversampling was 21.9% (95% CI: 17.0–26.8%). The most common barriers among non-insuring firms were absence of a legal mandate (51.8%) and high premium costs (49.6%). Firm size and organisational resource capacity are strongly associated with formal health-insurance provision. Phased Dhamani enrollment targeting large firms first, premium subsidies, and administrative support for micro- and small enterprises are the evidence-indicated policy responses.