In this section:

• Key points and introduction
• Developing the protocol of the review (C1-C23)
  • Setting the research question to inform the scope of the review (C1-C4)
  • Setting eligibility criteria for including studies in the review (C5-C13)
  • Selecting outcomes to be addressed for studies included in the review (C14-C18)
  • Planning the review methods at protocol stage (C19-C23)
• Performing the review (C24-C75)
  • Searching for studies (C24-C38)
  • Selecting studies to include in the review (C39-C42)
  • Collecting data from included studies (C43-C51)
  • Assessing risk of bias in included studies (C52-C60)
  • Synthesizing the results of included studies (C61-C73)
  • Assessing the quality of evidence and summarizing the findings (C74-C75)
  • Reference
• Citation