Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
Stata
Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
CNKI
Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
VIP
Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
Wanfang
Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
PubMed
Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
Embase
Specifically, clinical trial documents published on CNKI, VIP, Wanfang, PubMed, Embase, and the Cochrane Library from 2007-2017 were downloaded and analyzed using Stata 15.1 system. 
Cochrane Library