2.3.2. Data extraction and management

A standard form will be designed for data collection first of all. Two researchers will independently extract data of studies and record on the form. For the ambiguity of studies, it will be solved by expert discussion. We will contact authors for more information when necessary. The extracted data contain the first author, publication year, participants characteristics, interventions, duration of treatment, follow-up, outcome assessment, research results, adverse events, and other detailed information. If any details of the article are incomplete, we will contact the appropriate author for more information.