Results
The literature search generated a total of 21903 references: 6398 in PubMed, 9523 (5522 excluding conference abstracts) in Embase.com and 5982 in Clarivate Analytics/ Web of Science Core Collection. After removing duplicates of references that were selected from more than one database, 8746 references remained. Finally, 15 articles were included in this systematic review. The summary of the included articles is presented in Table 1. A flow chart of the search and selection process is presented in Figure 1 (included in Appendix A in the supplementary material).