| Date | Event | Description |
|---|---|---|
| 15 January 2015 | New citation required but conclusions have not changed | No new trials included. |
| 15 January 2015 | New search has been performed | Search updated. 'Summary of findings' tables have been incorporated. |
| 17 September 2012 | New citation required but conclusions have not changed | Review updated. |
| 17 September 2012 | New search has been performed | Search updated in July 2012. One further citation added to Excluded studies (Cousins 2012). |
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