He, Lixia
He, Junyong
Funding for this research was provided by:
The Health and Family Planning Commission of Sichuan Province (16PJ302)
Article History
Received: 5 November 2018
Accepted: 26 April 2019
First Online: 8 May 2019
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of Sichuan University. All participants provided written consent to take part in our study.
: Not applicable
: The authors declare that they have no competing interests.
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