Author Affiliations: Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, China (Drs Zhao, Zhang, and Lam); Department of Ophthalmology and Visual Sciences (Drs Zhao, A. H. Fan, Chen, D. S. P. Fan, and Lam), Institute of Chinese Medicine (Drs Leung and Lam), the Chinese University of Hong Kong, Hong Kong, China; Einhorn Clinical Research Center, New York Eye and Ear Infirmary, New York (Dr Ritch); and the Department of Ophthalmology, New York Medical College, Valhalla (Dr Ritch).
We thank Dr Wallace for his interest in our article.1 We agree that factors such as new or recent change in spectacle prescription might lead to visual improvement. However, this is less likely in our study, as children were eligible only if they had worn optimal spectacles for at least 16 weeks (washout period) prior to enrollment. During the washout period, we measured the visual acuity of all children every 5 (±1) weeks. Spectacle prescriptions were changed, if needed, according to standard clinical practice. The new spectacles must have been worn for at least 5 weeks prior to the screening visit. If the visual acuity was 1 line (or more) better than that of the previous visit, another screening visit would be scheduled. This process was repeated until no significant visual acuity improvement was detected between 2 consecutive visits.
Zhao J, Fan AH, Chen LJ, Fan DSP, Zhang M, Leung PC, Ritch R, Lam DSC. Acupuncture for Amblyopia: Study Design Considerations—Reply. Arch Ophthalmol. 2011;129(9):1242-1243. doi:10.1001/archophthalmol.2011.240