The strength of the present study is its generalisability.
In our study population, 20% of the patients had mild
COPD (GOLD grade I), and almost 70% of the patients
had moderate COPD (GOLD grade II). This sample is in
line with the distribution of COPD patients in primary
care [4]. Moreover, we did not exclude patients with comorbidities. Therefore, our study population is representative of the primary care population.