Table 3.

Visual Acuity Results in the Ahmed Baerveldt Comparison Study

	Ahmed Group N=104	Baerveldt Group N=101	P-value
Snellen VA, logMAR mean ± SD
Baseline (n=276)	1.07 ± 1.01	1.04 ± 1.00	.80†
3 years (n=205)	1.16 ± 1.07	1.19 ± 1.28	0.83†
Change at 3 years (n=205)	0.21 ± 0.88	0.26 ± 0.74	.66†
Loss of ≥ 2 Snellen lines at 3 years, n (%)*	36 (35%)	30 (30%)	0.55‡
Glaucoma	14 (39%)	9 (30%)
Retinal disease	8 (22%)	5 (17%)
Cataract	3 (8%)	4 (13%)
Other	8 (22%)	11 (37%)
Unknown	4 (11%)	1 (3%)

^*Patients may have more than one reason for decreased vision. In the one year manuscript, a change in acuity from counting fingers (CF) to hand motions (HM) and a change from HM to light perception (LP) was considered a two Snellen line loss. In the current manuscript these are considered a one Snellen line loss.

^†Two sided Student t-test

^‡Fisher exact test

VA = Visual Acuity, Logmar = Logarithm of the Minium Angle of Resolution visual acuity, SD = Standard Deviation