OBJECTIVES: People may be classified as vision-impaired or blind according to threshold levels of sight loss, with associated social and macro-economic consequences. We sought to understand these national statutory definitions and their impact on economic and patient burden, including variation by country.

METHODS: Blindness definitions and associated implications were identified from the World Health Organization, national government websites, health insurers, patient advocacy groups, and regulators in Brazil, Canada, France, Germany, Italy, Japan, Mexico, Spain, the US, and the UK.

RESULTS: Across all countries, visual field and visual acuity were included in blindness definitions, but threshold values for these parameters varied. Visual field thresholds for blindness varied from <10˚to 30˚, with a visual field threshold of 10˚used most frequently. Visual acuity thresholds for blindness varied from 20/200 Snellen (logarithm of the minimum angle of resolution (logMAR) 1.00) to 8/200 Snellen (logMAR 1.40), with 20/200 used most frequently. Multiple categories of vision impairment are defined in Germany, Japan, and the UK. In every country assessed, people registered as blind are eligible for tax exemptions (e.g., property tax) and welfare benefits; income tax reductions apply in all except Spain. The threshold visual acuity required for driving was typically 20/40 Snellen (0.3 logMAR). Similarly, visual field requirements for driving were specified in four countries (>120˚ to 150˚ uninterrupted horizontal field), and regulations in all other countries assessed suggest that any visual field defect results in driving disqualification.

CONCLUSIONS: Statutory blindness definitions, including thresholds of visual acuity and visual field, vary considerably by country. Blindness classification is associated with the societal costs of tax exemptions, tax reductions, and welfare payments. People with visual field loss are affected at an earlier stage due to driving disqualification.