Relative strength of association with chronic bronchitis of relevant genetic, lifestyle, clinical, sociodemographic characteristics, and relevant occupational exposures
| OR (95% CI) | p Value | |
| Smokingv not | 2.4 (1.7 to 3.4) | <0.001 |
| Inhalation v not | 1.7 (1.3 to 2.4) | <0.001 |
| Age (y, risk associated with a one unit change) | 1.04 (1.02 to 1.06) | 0.002 |
| Alcohol use, different categories referencing abstainers: | 0.003 | |
| Moderate use (1–21 drinks/week) | 0.8 (0.6 to 1.1) | |
| More than moderate (22–35 drinks/week) | 1.1 (0.7 to 1.6) | |
| Heavy use (>35 drinks/week) | 1.5 (0.96 to 2.2) | |
| Systolic blood pressure (mm Hg, risk associated with a one unit change) | 0.99 (0.98 to 0.997) | 0.003 |
| Long term exposure to cold and draught exposurev not | 1.4 (1.1 to 1.7) | 0.004 |
| Long term exposure to organic solvents vnot | 1.5 (1.1 to 2.1) | 0.008 |
| Height (cm, risk associated with a one unit change) | 0.98 (0.96 to 0.997) | 0.019 |
| Long term dust exposure v not | 1.5 (1.1 to 2.1) | 0.025 |
| NS-phenotype v others | 0.7 (0.5 to 0.999) | 0.044 |
Not in the final model (p>0.10): weight, retirement status, social class.
Variables are ordered according to strength of association with bronchitis after multivariate adjustment in a logistic regression model with backward elimination of variables.