| Date | Event | Description |
|---|---|---|
| 9 February 2018 | New citation required but conclusions have not changed | Risk of bias of 24 included studies was assessed and included in this first update. Quality of evidence is graded overall and reported in five 'Summary of findings' tables. |
| 24 November 2017 | New search has been performed | Search findings were updated until 24 November 2017. The updated search failed to identify any new trials. |
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