Delivery of WeChat-Based HIV Result e-Reports in Social Networks for Recruitment of High-Risk Population: Baseline Data From a Cluster Randomized Controlled Trial oleh Ju-Shuang Li, Yu-Zhou Gu, Feng-Su Hou, Yong-Heng Lu, Xiao-Ru Fan, Jia-Ling Qiu, Qing-Ling Yang, Jing Gu, Jing-Hua Li, Dong Roman Xu, Chun Hao