Table 2.

Parameter estimates from the Weibull and Log-logistic frailty model with normal random effect for studying circumcision's effect on HR-HPV clearance.

	Weibull				Log-logistic
	Est.	Std. Err.	95% C.I.	LR P-value (2-sided)	Est.	Std. Err.	95% C.I.	LR P-value (2-sided)
	0.96	0.16	(0.63, 1.28)		1.78	0.28	(1.23, 2.33)
	-1.59	0.34	(-2.25, -0.93)	< 0.0001	-1.30	0.17	(-1.63, -0.96)	< 0.0001
	0.42	0.23	(-0.02, 0.87)	0.04	0.45	0.22	(0.02, 0.89)	0.03
MSR2	1.56	0.35	(0.87, 2.24)		1.57	0.34	(0.90, 2.24)

^{The P-values were all obtained using likelihood ratio (LR) test.}

¹γ is a nuisance parameter, thus no P-value is presented as no hypothesis testing was performed. ²MSR: median survival time ratio (conditional on the random effect).

⁰Weibull model: MSR = exp(β₁); Log-logistic model: MSR = exp(β₁).