Introduction
Diabetic Retinopathy
DIABETIC RETINOPATHY
In clinical trials, central visual acuity (VA) is a surrogate outcome for vision-related functions such as reading, driving, watching television, and recognising faces. There are some disadvantages of creating a binary outcome (for instance, whether patients gain or lose ≥15 Early Treatment Diabetic Retinopathy Study [ETDRS] letter scores [equivalent to 3 Snellen lines]) from a continuous variable such as VA [An area under the curve (AUC)-type analysis [