Ou, Xiaofeng; Wang, Lijie; Yang, Jie; Tao, Pan; Wang, Cunzhen; Chen, Minying; Song, Xuan; Liu, Zhiyong; Zeng, Zhenguo; Huang, Man; Jiang, Xiaogan; Li, Shusheng; Chen, Erzhen; Liu, Lixia; Liao, Xuelian; Kang, Yan; On behalf of the Analgesia and Sedation Quality Control Subspecialty Group, National Center for Medical Quality Control in Critical Care Medicine