Table 7. Nine month grating acuity outcome for randomized patients

The Grating Acuity assessed with Teller acuity cards was judged as favorable or unfavorable (UF) in each eye at 9 months corrected age. The table shows the number of infants (N) categorized into those who had high risk prethreshold ROP in both eyes (bilateral) or only in one eye (asymmetric). The χ² test (χ-sq) for the infants with bilateral ROP was based on pairs for eyes with discordant outcomes (23 infants had an eye treated early with a favorable outcome and an eye managed conventionally with an unfavorable outcome; 8 infants had an eye treated early with a unfavorable outcome and an eye managed conventionally with an favorable outcome). Early treatment significantly improved grating visual acuity outcomes.

Republished with permission of the American Medical Association from Early Treatment For Retinopathy Of Prematurity Cooperative Group. Revised indications for the treatment of retinopathy of prematurity: results of the early treatment for retinopathy of prematurity randomized trial. Arch Ophthalmol 2003; 121:1684-94. Copyright ©2003 American Medical Association. All rights reserved.

              Eyes treated
              at high-risk    Conventionally
              prethreshold     managed eyes
             --------------   --------------
               N      % UF      N      % UF    χ-sq      p
             -----   ------   -----   ------   -----   -----
Bilateral     287     15.7     287     20.9    7.26    0.007
Asymmetric     43      7.0      36      8.3    0.05    0.82
             -----   ------   -----   ------   -----   -----
Total         330     14.5     323     19.5    6.60    0.01