Tomohiro Tamura, Hiroaki Satoh Division of Respiratory Medicine, Mito Medical Center, University of Tsukuba, Ibaraki, Japan We read with interest the article entitled “The lung function profile of once-daily tiotropium and olodaterol via Respimat® is superior to that of twice-daily salmeterol and fluticasone propionate via Accuhaler® (ENERGITO® study)” by Beeh et al.1 We would appreciate hearing from the authors on the three points as follows. First, the authors described inclusion criteria in the text and showed exclusion criteria in Table S1. However, we could not clearly understand how the authors excluded patients with bronchial asthma. We wondered whether there were a few patients with bronchial asthma included in this study, despite the study showing a superiority of tiotropium plus olodaterol in comparison with salmeterol plus fluticasone. Second, the authors showed that 59 of 288 patients were not randomized due to screening failure. We wondered whether a randomized error in such a large number of patients was unusual in a Phase III study and how the authors evaluated this. Third, as this study was a four-treatment, complete crossover study, the authors divided patients into four groups. We would appreciate hearing from the authors on what the effect of sequence had on the four treatments. Was there any effect of sequence on the results in this study? Please let us know how we should statistically evaluate its effect on the results. View the original paper by Beeh and colleagues.