3.1. Study selection
A total of 1110 records were identified from the four databases (PubMed, Scopus, EMBASE and Web of Science). After eliminating duplicate items, 616 records were obtained. After the selection phase, 38 records were selected independently by titles and abstracts. Twenty-one records were excluded: other types of studies, does not meet inclusion criteria, and conference abstracts. Finally, 17 studies were included. Figure 1 shows in detail the study selection process using a PRISMA flow diagram.
Figure 1. Flow diagram PRISMA of study selection process.
PRISMA 2020 flow diagram.