British Doctors Study
The British Doctors Study was a ground-breaking cohort study that confirmed the link between smoking tobacco and lung cancer. The link had been suspected but not statistically confirmed so in 1954, the UK Medical Research Council instructed its Statistical Research Unit to conduct a prospective study into the link. They sent a questionnaire on smoking habits to all registered British doctors. Of the 59,600 questionnaires mailed, 41,024 replies were received and 4,0701 (34494 males and 6207 females) were sufficiently complete to be included in the follow-up. Because of the limited sample size and limited tobacco consumption females were excluded from most reports, and the study has focused on the males.
The result was, that both lung cancer and coronary thrombosis (heart attacks) occurred markedly more often in smokers. The conclusion of the report showed that: ' A substantial progressive decrease in the mortality rates among non-smokers over the past half century (due to prevention and improved treatment of disease) has been wholly outweighed, among cigarette smokers, by a progressive increase in the smoker ν non-smoker death rate ratio due to earlier and more intensive use of cigarettes. Among the men born around 1920, prolonged cigarette smoking from early adult life tripled age specific mortality rates, but cessation at age 50 halved the hazard, and cessation at age 30 avoided almost all of it.'
Follow up studies where held up until 2001 and the link demonstrated in the study was instrumental in understanding the damaged caused by smoking. Thanks to Dr Sarah Berry our Fringe event speaker tonight who explained to us ‘How do we know which statistics we can trust?’