Funding for this research was provided by:
Michigan State University
Text and Data Mining valid from 2018-04-12
Received: 2 October 2017
Accepted: 4 April 2018
First Online: 12 April 2018
Ethics approval and consent to participate
: This study was approved by the ethics committee of Huainan Disease Prevention and Control Centre and Michigan State University Internal Review Board (IRB#× 15-413e), which are in accordance with the Declaration of Helsinki. Written, informed consent was obtained from participants according to these procedures prior to data collection.
: Not applicable.
: The authors declare that they have no competing interests.
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