Funding for this research was provided by:
Li Ka Shing Foundation-University of Oxford Global Health Programme (B9RSRT0-14)
Received: 21 February 2018
Accepted: 14 June 2018
First Online: 20 June 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Second Affiliated Hospital of Shantou University Medical College (with ref. no. Research-No. 4–2013) and the Oxford University Tropical Research Ethics Committee. Inform consent was waived as only patient records were reviewed.
: Not applicable.
: The authors declare that they have no competing interests.
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