All letters are subject to editing and may be shortened. General letters can be sent to bjgpdisc@rcgp.org.uk (please include your postal address for publication), and letters responding directly to BJGP articles can be submitted online via eLetters. We regret we cannot notify authors regarding publication.

For submission instructions visit: bjgp.org/letters

I read Punyadasa et al’s1 article with great interest. Partly because asthma is a serious medical condition that still causes excessive mortality,2 and partly because I have never been able to find strong evidence to support guidelines3 that asthma …