We evaluated the quality of the studies included by the Cochrane Handbook 5.2 standards and analyzed the data using the Cochrane Collaboration's RevMan 5.2 software.



RevMan 5.2
Randomized controlled trials (RCTs) were searched for in PubMed, EMBASE.com and the Cochrane Library through June 2013. 
PubMed
Randomized controlled trials (RCTs) were searched for in PubMed, EMBASE.com and the Cochrane Library through June 2013. 
EMBASE.com
Randomized controlled trials (RCTs) were searched for in PubMed, EMBASE.com and the Cochrane Library through June 2013. 
Cochrane Library