| Date | Event | Description |
|---|---|---|
| 11 August 2017 | New citation required but conclusions have not changed | focus of review changed from RCTs plus NRS to RCTs only; review updated according to Cochrane current criteria, new authors joined review team, no change to conclusions |
| 7 January 2017 | New search has been performed | searches rerun, five new studies included, three new studies excluded |
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