Evidence based case report: Twenty year cough in a non-smokerBMJ 1998; 316 doi: https://doi.org/10.1136/bmj.316.7145.1660 (Published 30 May 1998) Cite this as: BMJ 1998;316:1660
- Paul Glasziou (P.Glasziou@spmed.uq.edu.au), reader in clinical epidemiology
- University of Queensland Medical School, Queensland 4006, Australia
- Accepted 9 October 1997
Editorial by Godlee
Mrs V was a 66 year old woman who said she had had a non-productive cough almost daily for 20 years. This had been treated unsuccessfully in the past with antibiotics, but she was not taking any medication currently. Mrs V had good exercise tolerance, although she had an occasional wheeze at night. She was a non-smoker and had never lived with smokers. Her chest was normal on examination. Her peak expiratory flow rate was 500 (with a predicted value of 380), and her spirometry result was good and showed minimal (<5%) response to β agonist. Nevertheless, because asthma is an intermittent but common cause of cough, and because Mrs V had complained of nocturnal wheeze, I decided to try her on a β agonist aerosol (an alternative would have been an inhaled steroid, but the response to treatment would have taken longer). Meanwhile, I resolved to track down the evidence about other possible causes of Mrs V's cough.
Searching for evidence
The first step was to formulate an answerable clinical question1—one of aetiology, differential diagnosis, diagnostic test accuracy, prognosis, treatment, or prevention. Here the initial clinical question was one of differential diagnosis: what are the possible causes, and frequency, of a chronic …