Funding for this research was provided by:
Zhejiang Public Welfare Science and Technology Project (2015C33225)
Zhejiang Provincial Program for the Cultivation of High-Level Innovative Health Talents
Text and Data Mining valid from 2019-04-04
Received: 27 November 2018
Accepted: 20 March 2019
First Online: 4 April 2019
Ethics approval and consent to participate
: The study protocol was approved by the Research Ethics Committees of Hangzhou Centers for Disease Prevention and Control, Zhejiang, China. All the participants provided the written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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