The fact that Dr Julian De Havilland is the husband of Dr Eva Michalak was unfortunately inadvertently omitted from this print letter (BMJ 2012;344:e548).

This fact is made clear in the full response, and there is consequently no confusion with competing interests given as "None declared." I used this competing interests statement for the letter in the print journal as is usual practice. However, I forgot to add that Dr De Havilland is the husband of Dr Michalak to the shortened response for print, although I had intended to do so.

I apologise for the confusion caused.

Competing interests: I processed Dr De Havilland's rapid response for publication as a letter in the print journal