Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Flow diagram showing the overview of the search/selection process. The initial search in the three indexes identified a total of 450 records. After the exclusion of the papers that are not studies, the exclusion of the duplicated articles, and the abstract screening, we carried out a full text screening of 108 papers. Finally, 31 articles met our criteria and were selected for analysis.
