Analysis of multicenter clinical trials with very low event rates

Table 3 Type I error, mean estimated odds ratio (OR), convergence rate (%), and coverage of 95% confidence intervals when the number of centers was 5, the ICC was 0.025, the event rate was 10%, the participant distribution across centers was skewed, and the true OR was 1

Number of participants (n)	Measurement	Unadjusted	RE	MH	GEE	GEE-small sample correction
n = 200	Type I error	0.046	0.047	0.030	0.157	0.044
	MCSE (type I error)	0.003	0.003	0.002	0.005	0.003
	Mean	1	1	1	1	1
	MCSE (mean)	0.007	0.007	0.007	0.007	0.007
	Convergence	100	100	100	99.4	97.08
	Coverage	0.954	0.953	0.953	0.843	0.881
	MCSE (coverage)	0.003	0.003	0.003	0.005	0.005
n = 500	Type I error	0.049	0.050	0.037	0.160	0.050
	MCSE (type I error)	0.003	0.003	0.003	0.005	0.003
	Mean	1	1	1	1	1
	MCSE (mean)	0.004	0.004	0.004	0.004	0.004
	Convergence	100	100	100	99.9	99.08
	Coverage	0.951	0.950	0.95	0.840	0.877
	MCSE (coverage)	0.003	0.003	0.003	0.005	0.005
n = 1000	Type I error	0.044	0.045	0.039	0.149	0.048
	MCSE (type I error)	0.003	0.003	0.003	0.005	0.003
	Mean	1	1	1	1	1
	MCSE (mean)	0.003	0.003	0.003	0.003	0.003
	Convergence	100	100	100	99.98	99.6
	Coverage	0.956	0.955	0.955	0.851	0.884
	MCSE (coverage)	0.003	0.003	0.003	0.005	0.005
n = 5000	Type I error	0.047	0.048	0.042	0.154	0.055
	MCSE (type I error)	0.003	0.003	0.003	0.005	0.003
	Mean	1	1	1	1	1
	MCSE (mean)	0.001	0.001	0.001	0.001	0.001
	Convergence	100	100	100	100	99.98
	Coverage	0.953	0.952	0.952	0.846	0.878
	MCSE (coverage)	0.003	0.003	0.003	0.005	0.005

GEE generalized estimating equations, MH Mantel–Haenszel, RE random-effects (i.e., random center intercept), MCSE Monte Carlo standard errors

ISSN: 1745-6215