[1] Samarth, Social Sci Dept, Chennai, Tamil Nadu, India
[2] Sankara Nethralaya, Dept Ophthalmol, Chennai, Tamil Nadu, India
[3] Giridhar Eye Inst, Dept Ophthalmol, Cochin, Kerala, India
[4] Aditya Jyot Fdn Twinkling Little Eyes, Dept Ophthalmol, Mumbai, Maharashtra, India
[5] VMA Netra Niramay Niketan, Dept Ophthalmol, Haldia, W Bengal, India
[6] Moorfields Eye Hosp NHS Fdn Trust, NIHR Biomed Res Ctr, Dept Ophthalmol, London, England