MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov databases were searched. 
MEDLINE
MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov databases were searched. 
EMBASE
MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov databases were searched. 
CINAHL
MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov databases were searched. 
ClinicalTrials.gov