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 chart of the literature screening process. BMJ, British Medical Journal; WHO, World Health Organization; SIGN, Scottish Intercollegiate Guidelines Network; GIN, Guidelines International Network; JBI, Joanna Briggs Institute; CNKI, China National Knowledge Infrastructure.
