Usability of Wearable Devices With a Novel Cardiac Force Index for Estimating the Dynamic Cardiac Function: Observational Study oleh Hsiao, Po-Jen, Chiu, Chih-Chien, Lin, Ke-Hsin, Hu, Fu-Kang, Tsai, Pei-Jan, Wu, Chun-Ting, Pang, Yuan-Kai, Lin, Yu, Kuo, Ming-Hao, Chen, Kang-Hua, Wu, Yi-Syuan, Wu, Hao-Yi, Chang, Ya-Ting, Chang, Yu-Tien, Cheng, Chia-Shiang, Chuu, Chih-Pin, Lin, Fu-Huang, Chang, Chi-Wen, Li, Yuan-Kuei, Chan, Jenq-Shyong, Chu, Chi-Ming