Received: 31 January 2019
Accepted: 2 July 2019
First Online: 9 July 2019
Ethics approval and consent to participate
: Written informed consent was obtained from all participants prior to their participation. The research protocol was approved by the Ethics Committee of The Affiliated Huaian No.1 People’s Hospital of Nanjing Medical University. The ethical approval was consistent with the standards of the Declaration of Helsinki.
: Not applicable.
: The authors declare that they have no competing interests.