Table S6.

Multivariate model of predictors of patient’s disagreement^* with the statement “Smoking is the cause of most cases of COPD”: Continuing to Confront COPD International Survey, 2012–2013

Patient characteristic	Odds ratio (95% CI)
Smoking status
Current smoker	Ref
Former smoker	1.6 (1.3, 1.9)
Never smoker	4.4 (3.6, 5.4)
Exposed to dust or fumes from cooking, burning, mining, welding, etc, for a year or more
Yes	1.2 (1.0, 1.4)
No	Ref
Age (years)
40–49	1.8 (1.4, 2.2)
50–59	1.6 (1.3, 1.9)
60–69	1.1 (0.9, 1.4)
70+	Ref
Sex
Male	Ref
Female	1.5 (1.3, 1.7)
Education level
High school (secondary school) or less	Ref
Some/completed university or technical training	1.3 (1.1, 1.5)
Qualifying diagnosis
Physician-diagnosed COPD	0.6 (0.4, 0.7)
Physician-diagnosed chronic bronchitis	0.5 (0.4, 0.6)
Symptom-based definition of chronic bronchitis	Ref

Notes: All factors associated with disagreement in univariate analysis were entered into a backward elimination model; only statistically significant variables (displayed above) and country were retained in the final model;

^*strongly disagreed or somewhat disagreed with the statement.

Abbreviations: COPD, chronic obstructive pulmonary disease; CI, confidence interval; Ref, reference category.