Funding for this research was provided by:
Wellcome Trust (WT084754)
Received: 16 November 2016
Accepted: 16 January 2018
First Online: 25 January 2018
Ethics approval and consent to participate
: All research procedures with human participants were approved by the Institutional Ethics Committee of the Public Health Foundation of India, New Delhi. The study participants were well-informed of the aim and purpose of the study, and of their rights regarding participation. Participation was solely on a voluntary basis, and written informed consent was obtained from all participants before the interview. No incentives in the form of cash or in-kind were provided to participants.
: Not applicable
: The authors declare that they have no competing interests.
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