| Date | Event | Description |
|---|---|---|
| 23 August 2016 | New search has been performed | Results of 2012 and 2015 update searches added to the review. Two new studies added to included studies. |
| 23 August 2016 | New citation required but conclusions have not changed | Data from two new studies did not substantially alter results or change overall conclusions. |
| 10 April 2015 | Amended | Search updated, and 299 possibly related references were added to 'Classification pending references' of the review. |
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