This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables.
To the Editor.
—I was interested to read the editorial by Aiello et al on the diabetic retinopathy study in the Archives (90:347-349, 1973) and the letter by the same authors published in the American Journal of Ophthalmology (76:403, 1973). As they emphasize, the principle of applying light coagulation only to one randomly chosen eye, of patients with diabetic retinopathy is important in assessing the efficacy of this form of treatment: The "fellow eye" in ophthalmology is almost ideal as a control. May I make some other important and relevant points, standard practice in clinical trials, with apologies if the investigators have already incorporated them in their plan to do a difficult investigation?
—Since visual acuity will be an important criterion, the refractionist(s) must be unbiased when doing the very careful refraction required just before entry to, during, and at the end of the trial and beyond, ie,
Phillips CI. The Diabetic Retinopathy Study. Arch Ophthalmol. 1974;92(2):179. doi:10.1001/archopht.1974.01010010185023