“…1,11,13,21,27,28,30,35,47,51,54,75,78,89 Slightly more often, studies reported the degree of visual impairment (e.g., severe visual impairment, legal blindness) or fulfillment of certain criteria for low vision (e.g., the criteria for low vision of the WHO or the ICD criteria). 1,6,16,20,39,40,44,50,56,62,69,75,90,93,96,104,110,111,121 In some cases, authors quantified the number of participants with a certain degree of visual impairment, that is, how many participants had visual impairment and how many participants were blind. 32,39,74,85,90,97,108,123 Thirteen studies reported the number of participants that fell into a visual acuity range or reported the visual acuity of each individual participant, 7,8,12,13,15,…”