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. 2022 Mar 3;17:427–437. doi: 10.2147/COPD.S346591

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© 2022 Whittaker et al.

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Study design.

Notes: Baseline exacerbation groups include: none, 1 moderate (and no severe), 2 moderate (and no severe), 3+ moderate (and no severe), 1 severe (and any moderate), 2 severe (and any moderate) and 3+ severe (and any moderate) defined in the year prior to index date.

Abbreviations: CRD, current registration date; AECOPD, acute exacerbation of COPD; TOD, transfer out date.