Funding for this research was provided by:
Key Research Base Project of Humanities and Social Sciences of Colleges in Anhui Province (SK2018A0184, SK2017A0179)
Natural Science Fund of Education Department of Anhui Province (KJ2015B070by)
Text and Data Mining valid from 2020-04-05
Received: 13 September 2019
Accepted: 12 March 2020
First Online: 5 April 2020
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Bengbu medical college. Written informed consent was collected from parents or guardians and students. The study was performed in accordance with approved national guidelines.
: Not Applicable.
: The authors declare that they have no competing interests.