Use inclusion and exclusion criteria to screen studies.
Conduct the screening process in two stages:
Title/abstract screening
Full-text screening
Screening should be performed by at least two reviewers independently to achieve objectiveness. Any discrepancies should be resolved by a 3rd reviewer or discussion among the two reviewers to reach agreements.
The included references from the title and abstract screening will be moved forward to full text screening. PDFs need to be retrieved for each included reference for review. Any studies that are excluded after full text evaluation need to be noted with a rational for exclusion. All this should be recorded in the flowchart of study selection.