| Date | Event | Description |
|---|---|---|
| 18 December 2014 | New search has been performed | Four studies studies identified from updated search. One study included (Elliott 2005); three studies excluded (Brun 2011; Ma 1992; Latorre 2014). |
| 18 December 2014 | New citation required but conclusions have not changed | One new study included. Similar conclusions. |
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