Received: 2 April 2018
Accepted: 17 August 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: The procedures followed were in accordance with the ethical standards of the Committee of Xinxiang Medical University, and the study protocol was approved by the committee. The questionnaire had an introductory paragraph explaining the purpose of the survey and the name of the research centre conducting the research, and the responses were anonymous. The researchers’ contact details were given at the end of the questionnaire so that the participants could gain further details about the research if they wished. Completion and return of the questionnaire was viewed as consent to participate.
: Not applicable.
: The authors declare that they have no competing interests.
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