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. 2020 Mar 3;15:471–478. doi: 10.2147/COPD.S214410

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© 2020 Vaidya et al.

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(A) Difficulty score of the C-PPAC questionnaire in patients with and without LTOT. LTOT = long term oxygen therapy. (B) Difficulty score of the C-PPAC questionnaire according to the influence of rainfall.