Comparison of the distribution of asthma severity (%) based on different indexes applied to different populations
| Cohort of asthmatic patients, Quebec, Canada*(n = 139 283 person-years) | Cohort of asthmatic patients, France20†(n = 4333) | AIR America survey, USA21‡(n = 2509) | Cohort of asthmatic patients, Ontario, Canada7§(n = 1279) | |
|---|---|---|---|---|
| *Index based on dispensed medications and medical services for asthma. | ||||
| †Index based on symptoms and forced expiratory volume in 1 s (FEV1). | ||||
| ‡Index based on symptoms and the current state of asthma management. | ||||
| §Index based on reported daily medication use. | ||||
| Mild asthma | 63 | 66 | 59 | 28 |
| Moderate asthma | 23 | 21 | 22 | 49 |
| Severe asthma | 14 | 13 | 19 | 23 |