Funding for this research was provided by:
Agency for Healthcare Research and Quality (R21 HS021844)
Sun Yat-sen University Young Teachers' Scientific Research Program (51000-31121403)
Received: 17 August 2016
Accepted: 16 January 2018
First Online: 29 January 2018
Ethics approval and consent to participate
: This study is based on hospital level, publicly available information. We did not collect, analyze, or report any individual level, identifiable, human subject’s data. Hence this study is not considered human subject research. It was approved by the Institutional Review Board of the School of Public Health, Sun Yat-sen University.
: Not applicable.
: The authors declare that they have no competing interests.
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