| Date | Event | Description |
|---|---|---|
| 18 February 2019 | New search has been performed | Updated to include new trial and newer methods, including 'Summary of findings' table. |
| 7 June 2018 | New citation required and conclusions have changed | One new trial included (Williams 2017). |
| 18 September 2008 | Amended | Converted to new review format. |
| 14 February 2006 | New citation required and conclusions have changed | Substantive amendment |
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