| Date | Event | Description |
|---|---|---|
| 9 August 2017 | New search has been performed | Search updated. Six new studies included and 22 new studies excluded. Three new ongoing studies identified |
| 9 August 2017 | New citation required but conclusions have not changed | Search updated. Six new studies included and 22 new studies excluded. Three new ongoing studies identified. Text amended to reflect current Cochrane standards, and 'Summary of findings' table added. Feedback addressed. No change to conclusions |
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