Figure 3.

Treatment group difference in the mean change in amblyopic-eye visual acuity from baseline to 4 weeks according to baseline subgroups. Positive differences favor the binocular treatment group. Subgroup analyses were limited to participants who completed the 4-week outcome visit within the pre-defined analysis window (21 to <49 days after randomization). All subgroup factors were pre-specified. An analysis of covariance was performed to test the 2-way interaction between treatment group and each subgroup factor (baseline age and amblyopic-eye visual acuity were treated as continuous variables), adjusting for baseline amblyopic-eye visual acuity. P-values were not computed for categorical subgroup factors with fewer than 20 participants per treatment group in one or more subgroup levels. Statistical significance of the interaction term was based on a 2-sided alpha of 0.01.