Rapid Assessment of Avoidable Blindness (RAAB) Survey

Date of Completion: December 2022

Funder: Himalayan Cataract Project (HCP)

Aim: Measure the magnitude and causes of blindness and vision impairment and determine coverage and quality of cataract surgical services.

Background

Ethiopia has one of the highest burdens of blindness and vision impairment worldwide. However, the only nationwide blindness survey was conducted about 20 years ago in 2005/6. This research project provided representative, population-based estimate of the magnitude and causes of blindness and vision impairment in 50 years and older population through Rapid Assessment of Avoidable Blindness (RAAB) Survey in West Gojam Zone and Bahirdar City Administration.

Key Findings

• The adjusted prevalence of bilateral blindness was 2.8% (95% CI: 2.3%–3.4%), higher among women (3.4%, 95% CI: 2.6%–4.2%),) than men (2.3%, 95% CI: 1.6%–3.0%),). 

• Vision impairment affected 15.9% (women 16.7%, men 14.9%).

• Cataract (43.4%), glaucoma (14.8%), and age-related macular degeneration (13.9%) were the leading causes of blindness.

• Over 80% of blindness was avoidable.

• Refractive error prevalence was 1.8.% (95% CI 1.4%–2.3%), with 79.0% uncorrected.

• Effective Cataract Surgical Coverage (eCSC, <6/12 surgical threshold) was 13.0% (95% CI, 19.5%–16.5%) and effective Refractive Error Coverage (eREC) was 5.2% (95% CI, 0.3%–10.0%).

• Overall, 41.6% of cataract surgeries achieved a 'good' visual outcome (≥6/12 post-operative presenting visual acuity), increasing to 45.5% with pinhole correction.

• The overall disability prevalence was 5.7% (95% CI, 4.7%–6.6%), vision related disability prevalence was 3.6% (95% CI, 3.0%–4.3%).