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Rapid Assessment of Avoidable Blindness in India
John Neena1, Jose Rachel, Vashist Praveen
1Community Ophthalmology Unit, Dr RP Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, Delhi State, India.
Plos One
|August 7, 2008
Summary
Avoidable blindness in India affects 8.2% of the rural population, primarily due to cataracts and refractive errors. Early detection and intervention strategies are crucial for reducing the burden of visual impairment.
Area of Science:
- Ophthalmology
- Public Health
- Epidemiology
Background:
- Rapid assessment of avoidable blindness (RAAB) is a validated method for estimating the prevalence and causes of visual impairment.
- The study aimed to determine the magnitude and causes of avoidable blindness in India's population aged 50 and above in 2007.
Purpose of the Study:
- To assess the prevalence of blindness and severe visual impairment in individuals aged 50 years and older in India.
- To identify the primary causes of avoidable blindness and low vision within this demographic.
Main Methods:
- A follow-up survey was conducted in 16 districts previously surveyed 7-10 years prior.
- Stratified cluster sampling was employed, examining 100 individuals aged 50+ in each of the 25 selected clusters (20 rural, 5 urban).
- Presenting vision was assessed, with individuals <6/18 dilated and examined by an ophthalmologist.
Main Results:
- Out of 42,722 enumerated individuals (94.7% examined), 4.4% had severe visual impairment and 3.6% were blind.
- Prevalence of blindness and severe visual impairment was higher in rural residents (8.2%) compared to urban (7.1%), females (9.2%) vs. males (6.5%), and those over 70 years (20.6%).
- 88.2% of blindness was avoidable, with cataracts (81.9%) and uncorrected refractive errors (7.1%) being the leading causes.
Conclusions:
- Cataract and refractive errors are the principal causes of blindness and low vision in the Indian population aged 50+.
- Control strategies must prioritize interventions for cataract and refractive error correction.
- A significant proportion of the blindness and low vision burden in this population is avoidable.
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