| Date | Event | Description |
|---|---|---|
| 18 June 2015 | Amended | Minor corrections made |
| 4 August 2014 | New citation required but conclusions have not changed | Two new trials have been included (Fuller 2013; Wu 2013); conclusions remain unchanged |
| 4 August 2014 | New search has been performed | The searches were updated on 04 August 2014 |
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