Date	Event	Description
14 May 2008	Amended	Converted to new review format.
9 November 2006	New search has been performed	Searches conducted. Jenny Latte repeated the original searches. Twelve new studies were identified. A thirteenth study was sent to the review authors by a reader of the review. The review authors are awaiting publication of the fourteenth study. The review now has data for safety analysis.
31 January 2004	New search has been performed	Searches conducted. Original co‐author has been removed (Lisa Bickford) and new co‐author, G Jenny Latte (GJL) added. Michael Draper repeated the original search strategy up to September 2003. Ruth Foxlee repeated the original search strategy up to February 2004. Jenny Latte repeated the original search strategy in EMBASE up to February 2004. One new included study was identified. Fourteen new studies which were excluded were identified. Confidence intervals (CI's) have been added to the results section at the request of a Feedback comment.
5 January 2004	Feedback has been incorporated	Reply to feedback added to review
15 May 1999	New search has been performed	Searches conducted