Date	Event	Description
11 November 2015	New citation required and conclusions have changed	16 new included studies
7 July 2015	New search has been performed	This review was updated following a new search in July 2014 and a top up search in July 2015
9 May 2012	Amended	Line added to Acknowledgements section on behalf of CB
24 September 2009	New search has been performed	Updated with new included studies
24 September 2009	New citation required but conclusions have not changed	Updated, new authors
25 June 2008	Amended	Converted to new review format
1 November 2003	Amended	Also, in Issue 4, 2003, the result of the parent‐report meta‐analysis has been corrected from the previously published text from a non‐significant improvement of intervention to control of ‐0.29 (‐3.31 to ‐1.10) to a non‐significant improvement of intervention to control of ‐0.29 (‐0.55 to ‐0.02)
31 July 2003	Amended	Small errors in a previous version of this review were changed in Issue 3, 2003, to reflect incorrect setting of the WMD instead of the SMD statistic in the meta‐analyses and to align correct results in the meta‐view with incorrect ones in the text
22 November 2002	New citation required and conclusions have changed	Substantive amendment