Of smokers, enthusiasts, and bedbugs

People have been surveying smokers for years, and as a result there's a wealth of information still capable of yielding new insights or settling old scores. Two examples appear in this week's BMJ.

On p 1097 Richard Doll and colleagues use data from the British doctors cohort to lay to rest the suggestion that smoking might protect against dementia. Richard Doll has been studying the smoking habits of doctors since 1951, and data from the cohort were influential in prompting doctors to be one of the earliest groups to abandon smoking. In …