Text and Data Mining valid from 2018-03-30
Received: 17 September 2017
Accepted: 21 March 2018
First Online: 30 March 2018
Compliance with ethical standards
: Xinwei Han, Meipan Yin, Lei Li, Ming Zhu, Kewei Ren, Yu Qi, Xiangnan Li, and Gang Wu have no conflicts of interest or financial ties to disclose.
: This study was approved by the Ethics Committee and Medical Records Management Department of the First Affiliated Hospital of Zhengzhou University, Henan, China (Registration No. 2015-07).
: All patients gave written informed consent.