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. 2017 Mar 24;74(6):449–455. doi: 10.1136/oemed-2016-104157

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© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

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Spirometry patterns at exams 1 (2008–2010) and 2 (2013–2014) according to lower respiratory symptom pattern. Includes 454 participants with valid spirometry at both exams. χ² or Fisher’s exact tests were used to assess differences in the proportion with normal spirometry between symptom groups at exam 2. McNemar test was used to assess differences between exam 1 and exam 2 within each symptom group. *Comparison of persistent versus asymptomatic groups at exam 2. **Comparison of persistent versus resolved groups at exam 2.