Table 2.

Change in visual acuity over time for the implant and systemic treatment arms during the initial 2 years of follow-up (as-randomized analysis).

	Sample Size*	Estimate Mean(SE§)		Estimated Mean Change from Enrollment(SE§)		Estimated Treatment Effect† (95% CI§)	P-value
		Implant	Systemic	Implant	Systemic	Implant:Systemic
Primary Outcome: Visual acuity (letters read)	E=
Enrollment	475	61.0(2.5)	64.4(2.5)	n/a	n/a	n/a	n/a
6 months	443	66.9(2.3)	66.4(2.6)	5.88(1.07)	1.97(1.14)	3.91 (0.87, 7.02)	0.014
12 months	437	65.6(2.4)	67.7(2.6)	4.61(1.38)	3.33(1.23)	1.29 (−2.32, 5.01)	0.49
24 months	435	67.0(2.4)	67.6(2.6)	6.03(1.41)	3.23(1.41)	2.79 (−1.16, 6.68)	0.16
Visual acuity (letters read by the better eye)	N=
Enrollment	254	71.3(2.3)	75.4(2.0)	n/a	n/a	n/a	n/a
6 months	236	74.5(2.0)	76.8(2.2)	3.19(1.13)	1.43(0.97)	1.76 (−1.16, 4.68)	0.24
12 months	234	74.6(2.0)	77.1(2.3)	3.30(1.28)	1.67(1.06)	1.63 (−1.64, 4.89)	0.33
24 months	232	75.2(2.1}	77.3(2.2)	3.90(1.29)	1.92(1.12)	1.98 (−1.38, 5.35)	0.25

^*Sample size = the number of eyes (E) or individuals (N) with data available at each visit.

^§SE = standard error, CI = confidence interval.

^†At each of the follow-up time points, the treatment effect is the model-based comparison of within treatment group change from enrollment (the difference of differences). A positive number favors implant.