Table 5.

Operating characteristics of the different three‐arm designs for Pocock and O'?Brien Fleming design types with equal allocation: disjunctive power, conjunctive power and average sample number (ASN) under different parameter configurations and maximum sample size N for a disjunctive power of 0.9 under δ _A=0.5andδ _B=δ _C=0.

Boundary		Effect size			Disj.	Conjunctive power			ASN
Type	l 1	δ A	δ B	δ C	Power	Sep.	Sim.	Imp.	Sep.	Sim.	N
Pocock	−∞	0.5	0.5	0.5	0.99	0.72	0.49	0.60	330	279
		0.5	0.5	0	0.97	0.011	0.008	0.014	395	297
		0.5	0	0	0.90	0.003	0.001	0.003	431	336	464
		0	0	0	0.025	0.0007	0.0005	0.0010	463	461
O'Brien	−∞	0.5	0.5	0.5	0.98	0.80	0.54	0.76	373	334
Fleming		0.5	0.5	0	0.97	0.015	0.004	0.019	398	351
		0.5	0	0	0.90	0.003	0.0008	0.003	412	376	424
		0	0	0	0.025	0.0008	0.0007	0.0009	424	424