Funding for this research was provided by:
National Natural Science Foundation of China (71874137)
the Research Program of Shaanxi Soft Science (2015KRM117)
the Basic Scientific Research Funding of Xi’an Jiaotong University (SK2015007)
the National Program for Support of Top-notch Young Professionals and China Medical Board (15-227)
Text and Data Mining valid from 2018-11-20
Received: 8 February 2018
Accepted: 8 November 2018
First Online: 20 November 2018
Ethics approval and consent to participate
: We obtained verbal informed consent from each participate and signed the informed consent before investigation. In order to get the cooperation from the sample counties, the Shaanxi Health and Family Planning Commission delivered a document, and guiders from the sample counties would contact each participant who agreed to accept the interview, and make an appointment with them. The investigators then went to the participants’ house and collected information in our questionnaire, which means if we have participant’s questionnaire, we have got the participants’ consent. This method of consent in our study was approved by the Ethics Committee of Xi’an Jiaotong University Health Science Center (5th NHSS Approval No.2015–644), and it conformed to the ethics guidelines of the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.
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