A retrospective cohort review of 48,087 premature infants weighing <1500 gm between 24 to 27 weeks gestation, from 11 high income countries in Australia, New Zealand, Canada, Finland, Israel, Japan, Spain, Sweden, Switzerland, Tuscany (Italy) and the UK . By using Poisson and multivariate logistics regression analyses, pairwise comparisons of rates of retinopathy of prematurity (ROP) and ROP treatment by either laser or anti-VEGF were compared. Of these infants 81.8% survived to 32 weeks postmenstrual age (PMA) and 95% of the survivors were screened for ROP. Rates of ROP ranged from 25.2% (Switzerland) to 91% (Japan). The overall rate of ROP treatment was 24.9% (ranged from 4.3% in Switzerland to 30.4% in Japan). Adjusted risk ratios for ROP treatment were lower in Switzerland and Japan showed significantly higher ratios in all pairwise comparisons. The authors concluded that significant variations exist among these countries for ROP rates and treatment rates. They noted a general decline in ROP treatment except in the UK. It is not certain if these variations were due to the care practices, diagnosis and / or treatment threshold.