• COPD epidemiology
• health economist
• COPD exacerbations
• emphysema
• respiratory measurement
• smoking cessation
• tobacco and the lung

To screen or to target the missing millions with chronic obstructive pulmonary disease (COPD)? Moreover, what if we decide to invest in case-finding: do we get value for our money? Now, that’s the real question! First, however, we should establish what to pay for. Earlier research showed that one-third to half of COPD patients have not been diagnosed.1 2 Indeed, even if patients are already on the radar of a general practitioner (GP), opportunities to diagnose COPD are frequently being missed.3 COPD is still a major cause of severe patient symptoms (eg, breathlessness), costly hospital admissions and death.4 5 Notably, it is likely that earlier diagnosis and treatment to lessen breathlessness could reduce the risk of comorbidities associated with low physical activity developing and so contribute to healthier ageing.5 Those in favour of case-finding have, therefore, recently highlighted the need for early detection.6 Sceptics, on the other hand, argue that it is only useful if we can effectively slow down or halt the natural course of the disease.7

Over the last decade, multiple COPD case-finding strategies have been described.8 9 Most strategies seem effective, but generally few large, well-designed randomised controlled trials (RCTs) have been performed and outcomes have been very heterogeneous.10 Notably, this heterogeneity has limited our evidence on the optimal population at-risk to target, the best screening tools and diagnostic tests to use and, moreover, the cost-effectiveness of active case-finding. Limited evidence has also resulted in guideline committees and policymakers being hesitant in widely promoting case-finding.

This brings us back to the first question: what do the current guidelines actually tell us? The updated Global Initiative for Chronic Obstructive Lung Disease (GOLD) report discourages spirometry in asymptomatic populations without exposure to tobacco or other noxious stimuli. However, since 2019, it …