Funding for this research was provided by:
Queen Elizabeth Diamond Jubilee Trust, coordinated through the Commonwealth Eye Health Consortium- United Kingdom. (ITCRZC6812)
Received: 16 November 2018
Accepted: 22 April 2019
First Online: 21 May 2019
Ethics approval and consent to participate
: The ethics approval was obtained from the Ethics Review Committee of the London School of Hygiene and Tropical Medicine - UK and from the Ethics Review Committee of the National Eye Hospital - Colombo - Sri Lanka. Informed and written consent was obtained from all the participants for participation, audio recording and usage of anonymous quotations in the publication.
: Not applicable.
: The authors declare that they have no competing interests.
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