Funding for this research was provided by:
Weifang Medical University
Article History
Accepted: 1 March 2019
First Online: 21 March 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: Ethical approval was granted by the Ethics Committee of Weifang Medical University in April 2016.
: Informed consent was provided by all participants including in the study. The collection and transfer of data was carried out according to strict security and data encryption.