In the article entitled “Prediction of Acute COPD Exacerbation in the Swiss Multicenter COPD Cohort Study (TOPDOCS) by Clinical Parameters, Medication Use, and Immunological Biomarkers” [Respiration. 2022;101(5):441–54; DOI: 10.1159/000520196] by Huebner et al., it should be noted that authors Leuppi-Taegtmeyer A.B. and Leuppi J.D. contributed equally to the work.