Following guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic literature search in Web of Science, PubMed, Cochrane Library, and EMBase was carried out to identify relevant studies published up to May 2018. 
Web of Science
Following guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic literature search in Web of Science, PubMed, Cochrane Library, and EMBase was carried out to identify relevant studies published up to May 2018. 
PubMed
Following guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic literature search in Web of Science, PubMed, Cochrane Library, and EMBase was carried out to identify relevant studies published up to May 2018. 
Cochrane Library
Following guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic literature search in Web of Science, PubMed, Cochrane Library, and EMBase was carried out to identify relevant studies published up to May 2018. 
EMBase