Liu X, et al. - In this population-based observational cross-sectional study, 1461 children of age 7–19 years were studied to assess age-specific normative retinal oxygen saturation values and also to examine the associated factors in healthy Chinese school-aged kids with different refractive status. Authors observed the values of mean oxygen saturation of retinal arteries (SaO₂), veins (SvO₂) and differences between the arteries and veins (AVD), 83.7 ± 6.4%, 50.1 ± 5.4% and 33.6 ± 5.4%, respectively. They also noticed an increment in these values with age. They found girls with higher SvO₂ and lower AVD as compared to boys.