Indo-US case-control study of senile cataract--design and development.

Study design and development are presented for an investigation of risk factors for senile cataract in a collaborative Indo-US case-control study in New Delhi, India. This study emphasizes the relationship of nutritional status, as ascertained by biochemical assessment on plasma and red blood cells and by dietary history, to specific cataract types (nuclear, cortical, posterior subcapsular).