Funding for this research was provided by:
National Key R&D Program of China (MOST-2016YFC1303200, MOST-2016YFC1303202)
Clinical Capability Construction Project for Liaoning Provincial Hospitals (LNCCC-A01-2014)
Key Laboratory Programme of Education Department of Liaoning Province (LZ2015076)
Received: 1 October 2018
Accepted: 3 January 2019
First Online: 18 January 2019
Ethics approval and consent to participate
: The authors obtained the permission to analyzed data from SEER–Medicare program with the reference number D6-MEDIC-821, and masked the information could be linked to individual patients. The China Medical University’s institutional review board approved this study and the reference number was 96.
: Not applicable.
: The authors declare that they have no competing interests.
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