• Retina
• neovascularisation

We must admire the enormous amount of work and effort that was needed to put together the paper published in this issue of the British Journal of Ophthalmology by van Sorge et al (see page 937).1 The numbers, tables and statistics might be overwhelming but essentially reiterate the increased risk of retinopathy of prematurity (ROP) among babies with early gestational age and low birth weight. The other interesting and mixed messages are the relative reduction of visual impairment, presumably as a result of a combination of factors, and yet alarmingly the continued danger of not seeing and treating in time a significant number of babies at risk even in a well-organised healthcare system. This study is of particular relevance as it compares recent data with previous surveys carried out within the same Dutch society over a period of more than 30 years.2–6 Epidemiological studies, and diligent data collection and analysis, have played a pivotal role in advances in the understanding and management of ROP.