Date	Event	Description
10 June 2011	New search has been performed	This update has incorporated two new comparisons (comparing different radioisotopes and dose‐comparisons). It has also introduced several methodological improvements (changes in statistical methods, risk of bias assessment, summary of findings table). Search updated in July 2008 and further up to date in October 2010, and included 11 additional studies (821 additional participants). New studies are: Baczyk 2007, E13013 2000, Han 2002, Maxon 1991, Nair 1999, Nilsson 2007, Palmedo 2003, Resche 1997, Sartor 2004, Sciuto 2001, Smeland 2003.
10 June 2011	New citation required but conclusions have not changed	Conclusions have not changed significantly but readers of the review should re‐read the update as the conclusions have been revised and the methodology brought up to date.
9 July 2008	Amended	Converted to new review format.
27 July 2005	Amended	Minor revisions made to the review.