Data and reference search was conducted through the databases PubMed, EBSCOhost, Scopus, Cinahl and Google Scholar, as well as academic books, during the period of October 2017 to May 2018.
Heimilda var aflað í gegnum gagnasöfnin PubMed, EBSCOhost, Scopus, Cinahl og Google Scholar, ásamt fræðibókum, á tímabilinu október 2017 til maí 2018.