A systematic review of articles published using Web of Science (1950-January 2020); Medline via EBSCO (1992-January 2020); Science direct via ELSEVIER (1996-January 2020); SCOPUS (2004-January 2020); and PubMed (1946-January 2020 excluding Medline from 1992-January 2020) were included. 
Web of Science
A systematic review of articles published using Web of Science (1950-January 2020); Medline via EBSCO (1992-January 2020); Science direct via ELSEVIER (1996-January 2020); SCOPUS (2004-January 2020); and PubMed (1946-January 2020 excluding Medline from 1992-January 2020) were included. 
Medline via EBSCO
A systematic review of articles published using Web of Science (1950-January 2020); Medline via EBSCO (1992-January 2020); Science direct via ELSEVIER (1996-January 2020); SCOPUS (2004-January 2020); and PubMed (1946-January 2020 excluding Medline from 1992-January 2020) were included. 
Science direct via ELSEVIER
A systematic review of articles published using Web of Science (1950-January 2020); Medline via EBSCO (1992-January 2020); Science direct via ELSEVIER (1996-January 2020); SCOPUS (2004-January 2020); and PubMed (1946-January 2020 excluding Medline from 1992-January 2020) were included. 
SCOPUS
A systematic review of articles published using Web of Science (1950-January 2020); Medline via EBSCO (1992-January 2020); Science direct via ELSEVIER (1996-January 2020); SCOPUS (2004-January 2020); and PubMed (1946-January 2020 excluding Medline from 1992-January 2020) were included. 
PubMed