. 2021 Feb 16;7(2):e24204. doi: 10.2196/24204
©Dayong Gu, Jianan He, Jie Sun, Xin Shi, Ying Ye, Zishuai Zhang, Xiangjun Wang, Qun Su, Wenjin Yu, Xiaopeng Yuan, Ruiling Dong. Originally published in JMIR Public Health and Surveillance (http://publichealth.jmir.org), 16.02.2021.
This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Public Health and Surveillance, is properly cited. The complete bibliographic information, a link to the original publication on http://publichealth.jmir.org, as well as this copyright and license information must be included.