Date	Event	Description
25 June 2013	Amended	Minor edits
17 January 2013	New search has been performed	New search with one new study.
1 June 2012	New citation required and conclusions have changed	This review update involves new authors. The search was updated to include studies up to March 2012. The protocol has been updated to exclude high doses of folic or folinic acid > 7 mg/week in order to obtain a better estimate of effect in doses currently used in clinical practice. As a result, three previously included studies have been removed from the meta‐analysis.
11 June 2011	New citation required but conclusions have not changed	This review update involved new authors. All analyses were new but the conclusions did not change.
6 September 2008	Amended	Converted to new review format.
29 August 2007	New citation required and conclusions have changed	Substantive amendment