Table 6.

Empirical global power, power for each endpoint and proportion of terminating the trial early using O’Brien-Fleming boundaries and assuming unequal allocation of the type I error rate of 0.03 for PFS and 0.02 for OS; results based on 10,000 simulations

Type of Copula	τ	Empirical Global Power	PFS			OS
			1st Interim	Final Analysis	Power	1st Interim	Final Analysis	Power
Independence	0	0.978	0.121	0.745	0.866	0.193	0.832	0.834
Normal	0.10	0.971	0.124	0.748	0.872	0.216	0.832	0.834
	0.30	0.952	0.129	0.736	0.865	0.204	0.826	0.827
	0.50	0.932	0.132	0.732	0.864	0.210	0.836	0.837
	0.70	0.918	0.120	0.748	0.868	0.206	0.840	0.841
Frank	0.10	0.970	0.123	0.740	0.863	0.209	0.833	0.834
	0.30	0.952	0.121	0.739	0.860	0.211	0.834	0.831
	0.50	0.936	0.121	0.749	0.869	0.205	0.831	0.831
	0.70	0.917	0.130	0.739	0.869	0.217	0.835	0.836
Gumbel	0.10	0.970	0.125	0.744	0.869	0.216	0.832	0.833
	0.30	0.950	0.124	0.749	0.873	0.204	0.832	0.833
	0.50	0.930	0.122	0.745	0.866	0.208	0.837	0.838
	0.70	0.908	0.122	0.748	0.870	0.207	0.829	0.831