Table 3.

Random effects Poisson regression model.

Predictor	Estimated referral ratio	Standard error	95% CI	P-value
Intervention	0.812	0.065	0.694 to 0.950	0.009
Fundholder	1.009	0.087	0.852 to 1.195	0.919
Year	0.999	0.053	0.899 to 1.109	0.979
Baseline rate (per 1 per 1000)	1.165	0.021	1.125 to 1.206	<0.001
Sigma_u	0.185	0.050	0.109 to 0.313	0.002