Measuring clinical progression in MCI and pre-MCI populations: enrichment and optimizing clinical outcomes over time

Table 2 Sample sizes for different treatment effect sizes and different scale sensitivities to decline

		Mean-to-standard deviation ratio of change over time (coefficient of variation)
Sample size per group	0.2 (5)	0.3 (3.3)	0.4 (2.5)	0.5 (2)	0.6 (1.7)	0.7 (1.4)	0.8 (1.3)	0.9 (1.1)	1 (1)
Percentage effect relative to placebo
20	9,812	4,361	2,453	1,570	1,091	802	614	485	393
25	6,280	2,791	1,570	1,005	698	513	393	311	253
30	4,361	1,939	1,091	698	485	357	274	217	176
35	3,204	1,424	802	513	357	263	202	160	130
40	2,453	1,091	614	393	274	202	155	123	100
45	1,939	862	485	311	217	160	123	97	79
50	1,570	698	393	253	176	130	100	79	64
55	1,298	577	325	209	146	107	83	66	53
60	1,091	485	274	176	123	90	70	55	45
65	929	413	234	150	105	77	60	47	39
70	802	357	202	130	90	67	52	41	34
75	698	311	176	113	79	58	45	36	29
80	614	274	155	100	70	52	40	32	26
85	544	243	137	88	62	46	35	28	23
90	485	217	123	79	55	41	32	25	21
95	435	195	110	71	50	37	29	23	19
100	393	176	100	64	45	34	26	21	17

ISSN: 1758-9193