Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
PubMed
Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
Web of Science
Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
MEDLINE
Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
EMBASE
Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
China National Knowledge Infrastructure
Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
Wanfang database
Electronic searches of clinical randomized controlled trials in PubMed, Web of Science, MEDLINE, EMBASE, China National Knowledge Infrastructure, Wanfang database, and China Scientific Journal Database (VIP) were conducted. 
China Scientific Journal Database (VIP)
Relevant data were extracted, and a meta-analysis was performed using Reviewer Manager 5.4.



Reviewer Manager 5.4