Quality assessment of the individual studies.

: The item is met.
○: The item is not met.
1. Describe the locations.
2. Describe periods of recruitment, follow-up, and data collection.
3. Give the eligibility criteria, and the sources and methods of selection of participants.
4. Involve the available data on outcomes.
5. Report numbers of individuals at each stage of study.
6. Give reasons for non-participation at each stage.
7. Give characteristics of study participants.