Table 3. Sample sizes required for 80% power to detect effect.

Each cell denotes the total sample size required. For example, if HR is 1.5 and 20% of individuals are treated, a study requires a total of 459 patients (367 untreated, 92 treated).

	Proportion of individuals assigned to treatment
HR	0.1	0.2	0.3	0.4	0.5
1.1	13029	7296	5534	4821	4608
1.2	3701	2063	1558	1351	1286
1.3	1856	1030	774	668	633
1.4	1170	646	484	416	393
1.5	835	459	342	293	275
2.0	335	180	131	110	102
3.0	171	88	62	50	45