Table 2

Targeted power = 90%

Std ES	w = 0.010		w = 0.025		w = 0.050		w = 0.075		w = 0.100
Std ES	Nunadj	Extra	Nunadj	Extra	Nunadj	Extra	Nunadj	Extra	Nunadj	Extra
0.2	26536	126	10779	49	5533	23	3789	14	2921	10
0.4	6636	126	2697	48	1385	23	949	15	732	10
0.6	2951	126	1200	49	617	23	423	15	327	10
0.8	1661	127	676	49	348	23	239	15	185	10
1.0	1064	128	434	49	224	23	154	15	119	11
1.2	739	129	302	50	156	24	108	14	84	10
1.4	544	130	222	51	115	24	80	15	62	11
1.6	417	131	171	51	89	24	62	15	48	11
1.8	330	133	135	52	71	24	49	15	39	10
2.0	268	134	110	52	58	24	40	16	32	11
2.2	222	136	92	52	48	25	34	15	27	11
2.4	187	138	77	54	41	25	29	16	23	11
2.6	159	142	66	55	35	26	25	16	20	11
2.8	138	144	57	56	31	26	22	16	18	11
3.0	120	147	50	57	27	27	19	17	16	11

Targeted power = 80%

Std ES	w = 0.010		w = 0.025		w = 0.050		w = 0.075		w = 0.100
Std ES	Nunadj	Extra	Nunadj	Extra	Nunadj	Extra	Nunadj	Extra	Nunadj	Extra
0.2	19823	82	8053	32	4133	16	2831	10	2183	7
0.4	4958	82	2015	32	1035	15	710	9	547	7
0.6	2205	82	897	32	461	16	317	9	245	7
0.8	1241	83	506	32	261	15	179	10	139	7
1.0	795	83	324	33	168	15	116	9	90	7
1.2	553	84	226	33	117	16	81	10	63	7
1.4	407	84	167	32	87	15	60	10	47	7
1.6	312	86	128	33	67	16	47	10	37	7
1.8	247	87	102	33	53	16	37	10	29	7
2.0	201	88	83	34	44	16	31	10	24	7
2.2	166	90	69	35	37	16	26	10	21	7
2.4	140	91	58	36	31	17	22	11	18	7
2.6	120	93	50	36	27	17	19	11	16	7
2.8	104	95	44	36	24	17	17	11	14	7
3.0	91	97	38	38	21	17	15	11	12	8

Table 2: The unadjusted sample size (N_unadj) and the additional sample required (extra) as a function of targeted power, standardized effect size (Std ES) and sampling weight for the exposure group (w). A two-sided two-sample t - test was used for hypothesis testing at the α = 0.05 level.