Funding for this research was provided by:
National Natural Science Foundation of China (71373090)
Health Family Planning Commission scientific research project of Hubei Province (WJ2015GA001)
Text and Data Mining valid from 2018-04-04
Received: 22 January 2017
Accepted: 15 March 2018
First Online: 4 April 2018
Ethics approval and consent to participate
: The study protocol was approved by the Ethics Committee of Tongji Medical College Institutional review Board, Tongji Medical College, Huazhong University of Science and Technology (Wuhan, Hubei, China) and was carried out in accordance with the principles of the Declaration of Helsinki. All respondents were provided with written informed consent form, and all questionnaires were filled in by respondents anonymously.
: Not applicable.
: The authors declare that they have no competing interests.
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