Fig. 1.
PRISMA diagram for the systematic literature review. PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-Analyses [15]. aThe category “Other” includes duplicate references and conference abstracts before 2017
PRISMA diagram for the systematic literature review. PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-Analyses [15]. aThe category “Other” includes duplicate references and conference abstracts before 2017