[Zhu, Zhenggang] School of Nursing, Wenzhou Medical University, Ouhai District, Wenzhou, Zhejiang, China. Electronic address: 897846734@qq.com
[Ji, Binbin] School of Nursing, Hunan University of Chinese Medicine, Yuelu District, Changsha, Hunan, China
[Tian, Jun] Geriatric Department, Xiangya Hospital of Central South University, Kaifu District, Changsha, Hunan, China
[Yin, Ping] Hunan Maternal and Child Health Hospital, Kaifu District, Changsha, Hunan, China