| Date | Event | Description |
|---|---|---|
| 8 February 2017 | New citation required but conclusions have not changed | Conclusions not changed. |
| 8 February 2017 | New search has been performed | New author added. Searches updated. Background section revised, updated and new references added. Primary objective for review and primary outcome defined. Searches updated, PRISMA diagram added. We identified no new studies: the review has nine included studies involving 3137 participants. We have edited and updated the text and added 'Risk of bias' tables and a 'Summary of findings' table. |
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