| Date | Event | Description |
|---|---|---|
| 1 April 2019 | New citation required but conclusions have not changed | Small studies added, no change to conclusions |
| 30 July 2018 | New search has been performed | Four new studies added |
| 9 March 2011 | New citation required and conclusions have changed | Four new studies added |
| 9 October 2008 | Amended | Converted to new review format. |
| 22 May 2006 | New citation required and conclusions have changed | Substantive amendment |
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