- Plain English summary
- Scientific summary
- Chapter 1. Background
- Chapter 2. Objectives
- Chapter 3. Methods
- Chapter 4. Findings
- Chapter 5. Discussion
- Chapter 6. Conclusions
- Acknowledgements
- References
- Appendix 1. Inclusion and exclusion criteria
- Appendix 2. Example search strategy (MEDLINE)
- Appendix 3. List of studies excluded at full-text stage
- Appendix 4. Data extraction fields
- List of abbreviations