Gao, Feifei
Yao, Yuan
Yao, Chengwen
Xiong, Yan
Ma, Honglin
Liu, Hongbo
Funding for this research was provided by:
The Social Science Planning Foundation of Liaoning Province, China (L16CSH002)
The Natural Science Foundation of Liaoning Province, China (20170540359)
Article History
Received: 18 October 2018
Accepted: 24 July 2019
First Online: 1 August 2019
Ethics approval and consent to participate
: This study was conducted according to the Declaration of Helsinki. The study protocol was examined and approved by the ethics committee of Jinzhou Medical University [No: 2016–08], and it followed ethical standards. The written form approval from officials of all selected schools was obtained. The written informed consent had been obtained from the parents or guardians on behalf of the adolescents to participate in the study. Before administering any study-related questionnaires, all participants also signed an informed consent form.
: Not applicable.
: The authors declare that there are no competing interests.