It describes a tool designed to support general practitioners (GPs) in diagnosing their patients with suspicion of obstructive respiratory disease. Misdiagnoses and under-diagnoses of asthma and COPD are common. Many current diagnostic tools are not based on real-life data and hence lack generalisability to clinical practice. The tool was developed by analysing real-life data from 9,297 primary care patients who were diagnosed by a pulmonologist. These patients visited their GP with respiratory symptoms and were referred to an Asthma/COPD(AC)-service for primary care in the Netherlands for a diagnostic assessment according to a strict protocol. A local pulmonologist used the results from this assessment to diagnose the patients. These diagnoses were the starting point for this desktop tool. No exclusion criteria were used, all patients assessed by the AC-service were included for the development of the tool. Statistical analyses were used to evaluate which parameters predicted asthma, COPD, Asthma/COPD overlap syndrome (ACOS) or other.
Metting and colleagues showed that most patients in the Dutch Asthma/COPD-service could be correctly diagnosed with this tool (asthma 79% correct, COPD 85% correct, ACOS 32% correct). The tool was validated in another primary care population (n=3215) and showed a comparable accuracy (asthma 78%, COPD 83%, ACOS 24%).