Global estimates on the number of people blind or visually impaired by Uncorrected Refractive Error: A meta-analysis from 2000 to 2020

Julie-Anne Little, Rupert R. A. Bourne , VLEG Vision Loss Expert Group

Research output: Contribution to journalSpecial issuepeer-review

2 Downloads (Pure)


Uncorrected refractive error (URE) is a readily treatable cause of visual impairment (VI). This study provides updated estimates of global and regional vision loss due to URE, presenting temporal change for VISION 2020

Data from population-based eye disease surveys from 1980–2018 were collected. Hierarchical models estimated prevalence (95% uncertainty intervals [UI]) of blindness (presenting visual acuity (VA) < 3/60) and moderate-to-severe vision impairment (MSVI; 3/60 ≤ presenting VA < 6/18) caused by URE, stratified by age, sex, region, and year. Near VI prevalence from uncorrected presbyopia was defined as presenting near VA < N6/N8 at 40 cm when best-corrected distance (VA ≥ 6/12).

In 2020, 3.7 million people (95%UI 3.10–4.29) were blind and 157 million (140–176) had MSVI due to URE, a 21.8% increase in blindness and 72.0% increase in MSVI since 2000. Age-standardised prevalence of URE blindness and MSVI decreased by 30.5% (30.7–30.3) and 2.4% (2.6–2.2) respectively during this time. In 2020, South Asia GBD super-region had the highest 50+ years age-standardised URE blindness (0.33% (0.26–0.40%)) and MSVI (10.3% (8.82–12.10%)) rates. The age-standardized ratio of women to men for URE blindness was 1.05:1.00 in 2020 and 1.03:1.00 in 2000. An estimated 419 million (295–562) people 50+ had near VI from uncorrected presbyopia, a +75.3% (74.6–76.0) increase from 2000

The number of cases of VI from URE substantively grew, even as age-standardised prevalence fell, since 2000, with a continued disproportionate burden by region and sex. Global population ageing will increase this burden, highlighting urgent need for novel approaches to refractive service delivery.
Original languageEnglish
Early online date4 Jul 2024
Publication statusPublished online - 4 Jul 2024

Bibliographical note

© 2024. The Author(s).

Data Access Statement

The data that support the findings of this study are not openly available due to reasons of sensitivity and are available from the coordinator of the Vision Loss Expert Group (Professor Rupert Bourne; [email protected]) upon reasonable request. Data are located in controlled access data storage at Anglia Ruskin University.


  • Epidemiology
  • Public health


Dive into the research topics of 'Global estimates on the number of people blind or visually impaired by Uncorrected Refractive Error: A meta-analysis from 2000 to 2020'. Together they form a unique fingerprint.

Cite this