ROP: A cautionary tale: What we know and what we think we know

Retinopathy of prematurity is a complex disease with many subtleties and considerable individual variation. In order to obtain highly reliable evidence as to the nature of ROP, rigorous, randomized, controlled, multicenter trials that enroll a large number of eligible subjects are required. Fortunately, such trials have been conducted and have yielded a wealth of information. It is essential to critically evaluate these trials as well as other levels of scientific evidence to determine what our current state of knowledge is. This review focuses on what we know as fact and what may be common practice or empirical knowledge not based on rigorous evidence.