Funding for this research was provided by:
Health Services Research Competitive Research Grant, National Medical Research Council, Singapore
Singapore Ministry of Health’s National Medical Research Council under the Centre Grant Programme – Singapore Population Improvement Centre (NMRC/CG/C026/2017_NUHS)
Received: 5 June 2018
Accepted: 16 October 2018
First Online: 25 October 2018
Ethics approval and consent to participate
: Ethical approval was provided by the National University of Singapore Institutional Review Board, SingHealth Centralized Institutional Review Board and the National Health Group Domain Specific Review Board. Written informed consent was collected from all participants in S3.
: Not applicable
: The authors declare that they have no competing interests.
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