| Date | Event | Description |
|---|---|---|
| 22 November 2021 | New citation required but conclusions have not changed | The review has been updated. |
| 22 November 2021 | New search has been performed | This is an update of an existing Cochrane Review (Appleton 2015). We used the same methods as in the previous review with some refinements, as detailed in the section on 'Differences between protocol and review'. The update includes 9 independent studies (from 8 randomised controlled trials) published since 2015, in addition to the 26 independent studies (from 20 trials) included in the previous review. |
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