Date	Event	Description
25 September 2017	New citation required and conclusions have changed	1. The addition of 42 new studies changed conclusions with respect to the effect for women, and enabled further subgroup analyses. 2. The review authorship changed.
25 September 2017	New search has been performed	1. The search was updated in September 2017 and 42 new trials (24,057 participants) were included, bringing the total to 69 included studies (33,642 participants). Two trials in the original review were excluded from this update. 2. The review has been substantially revised in accordance with Cochrane guidance, including the implementation of GRADE assessment, creation of 'Summary of findings' tables for the main comparisons, and further subgroup analyses.
28 July 2009	Feedback has been incorporated	We have replied to feedback from Dr Anders Beich
19 June 2008	Amended	corrected figures, estimates and add minor changes
29 April 2008	Amended	little changes
29 April 2008	New search has been performed	Add one study but conclusions are not changed
15 February 2007	New citation required and conclusions have changed	Substantive amendment