MRC dyspnoea score | 0.4 (0.2 to 0.6) | <0.001 | 0.2 (0.0 to 0.4) | 0.022 |
Do you usually cough on most days for 3 consecutive months or more during the year? | 0.4 (0.2 to 0.7) | 0.001 | 0.3 (0.0 to 0.5) | 0.026 |
Do you bring up phlegm on most days for 3 consecutive months or more during the year? | 0.5 (0.2 to 0.7) | <0.001 | 0.4 (0.1 to 0.6) | 0.006 |
Are you troubled by shortness of breath when hurrying on level ground or walking up a slight hill? | 0.2 (0.0 to 0.5) | 0.037 | 0.1 (−0.1 to 0.4) | 0.290 |
Have you had wheezing or whistling in your chest at any time during the past 12 months? | 0.3 (0.0 to 0.7) | 0.022 | 0.2 (−0.1 to 0.4) | 0.240 |
Apart from when you have a cold does your chest ever sound wheezy or whistling? | 0.3 (0.1 to 0.6) | 0.014 | 0.2 (−0.1 to 0.4) | 0.180 |
During the past 12 months have you had pneumonia? | 0.2 (−0.1 to 0.7) | 0.180 | 0.2 (−0.2 to 0.6) | 0.280 |
Number of NHANES questions (answered ‘Yes’) | 0.4 (0.2 to 0.6) | <0.001 | 0.3 (0.1 to 0.5) | 0.010 |
More than three NHANES questions (answered ‘Yes’) | 0.4 (0.1 to 0.7) | 0.001 | 0.3 (0.0 to 0.5) | 0.041 |
Lung function | | | | |
FEV1/FVC <0.7 | 0.4 (0.0 to 0.7) | 0.013 | 0.3 (0.0 to 0.5) | 0.024 |