Rapid responses are electronic letters to the editor. They enable our users to debate issues raised in articles published on thebmj.com. Although a selection of rapid responses will be included online and in print as readers' letters, their first appearance online means that they are published articles. If you need the url (web address) of an individual response, perhaps for citation purposes, simply click on the response headline and copy the url from the browser window. Letters are indexed in PubMed.
Please note that in the second paragraph of our Letter to the Editor
of BMJ, the final parenthesis of sentence seven should read "(~15%)"
rather than "(9%)" and the order of references 5 and 6 should be
DMS has previously (>3 years ago) received research grant funding from GSK and Sanofi-Pasteur.
No competing interests
25 November 2009
Danuta M Skowronski
BC Centre for Disease Control, Vancouver, British Columbia, Canada