| Date | Event | Description |
|---|---|---|
| 5 May 2012 | New search has been performed | Review update. New articles from latest search included. |
| 18 September 2010 | New citation required and conclusions have changed | Authors changed. Updated and restriction inclusion to RCTs |
| 10 September 2008 | Amended | Converted to new review format. |
| 25 November 2004 | New citation required and conclusions have changed | Substantive amendment |
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