Date	Event	Description
1 February 2013	New search has been performed	New literature search done
28 January 2013	New citation required but conclusions have not changed	A new search was performed which identified 3 new eligible studies (Clini 2002; McEvoy 2009; Sin 2007). One trial is listed as 'awaiting classification' until we can clarify the methods used in their study. The review has been re‐written and there has been a change to the list of authors and the review now also contains long‐term data (after 12 months).
13 August 2008	Amended	Converted to new review format.
2 January 2002	New citation required and conclusions have changed	Substantive amendment