Rapid assessment of cataract blindness in India.

28,055 persons aged 50 yrs+ from seven states in India were surveyed by a rapid assessment technique for cataract blindness. The prevalence of bilateral blindness (vision < 6/60 in the better eye) was 11.68 percent (95% C.I. 10.54-12.81). The age-gender adjusted blindness prevalence rate was 11.04 percent (95% C.I. 11.033-11.044). Age and occupational status were associated with blindness prevalence. Cataract was the commonest cause of low vision and blindness in this population. Respondents aged 60-69 years had a 2.74 times higher risk, while those aged 70 years+ had a 4.86 times higher risk of being blind, compared to those 50-59 years. Productively employed individuals had lowest blindness rates. Blindness rates were five times higher among respondents who were not working and two times higher among those engaged solely in household activities. The prevalence of cataract was 43.32 percent (95% C.I. 41.14-45.50) among those aged 50+ years. The prevalence increased with increasing age. Gender did not influence the prevalence of cataract in the present survey. Extrapolating from the present survey, it is estimated that 11.9 million blind people (vision < 6/60 in the better eye) in India are in urgent need of cataract surgery.