| Date | Event | Description |
|---|---|---|
| 17 January 2013 | New citation required and conclusions have changed | 13 new studies added. Changes made in review conclusions in relation to short course interventions. Summary of findings table added |
| 17 January 2013 | New search has been performed | Literature searches rerun |
| 10 March 2009 | Amended | Spelling correction |
| 5 September 2008 | Amended | Converted to new review format. |
| 12 October 2006 | New citation required and conclusions have changed | Substantive amendment |
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