Effectiveness of Digital Health Interventions for Chronic Obstructive Pulmonary Disease: Systematic Review and Meta-Analysis - Miaoqing Zhuang; Intan Idiana Hassan; Wan Muhamad Amir W Ahmad; Azidah Abdul Kadir; Xiaodong Liu; Furong Li; Yinuo Gao; Yang Guan; Shuting Song (Journal of Medical Internet Research)