Received: 3 November 2019
Accepted: 3 April 2020
First Online: 21 April 2020
Ethics approval and consent to participate
: This study was approved by the Research and Ethics Review Committee of Yidu Central Hospital of Weifang (January 18, 2017; Number: 2017–15). It was performed in strict accordance with the ethical standards of the Declaration of Helsinki. All subjects signed written informed consent.
: Written informed consent for publication was collected from each participant.
: The authors declare they have no competing interests.