| Date | Event | Description |
|---|---|---|
| 7 July 2015 | New citation required but conclusions have not changed | Search updated |
| 30 June 2015 | Amended | Added Summary of findings tables in lieu of previous 'Sensitivity analysis summary' |
| 26 June 2015 | New search has been performed | Search updated; no new studies found Added publication (Lanza 2013) for previously included conference presentation |
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