Table 3.

Power of the study to detect significant differences using a relative risk of 0.5

% in standard care group losing 3 or more lines of visual acuity over 12 months	Power to detect RR of 0.5
10%	0.35
20%	0.58
30%	0.81
40%	0.94
50%	0.99
60%	1
70%	1
80%	1
90%	1

RR, Relative risk.