Table 3.
Maximum acceptable exacerbations and maximal acceptable onset time by disease
| Attribute | Level | Maximum acceptable exacerbations | Maximum acceptable onset time | ||
| Mean (95% CI)* | Mean (95% CI)† | ||||
| Asthma (n=810) | COPD (n=1147) | Asthma (n=810) | COPD (n=1147) | ||
| Number of exacerbations | 3 per year | – | – | Reference | Reference |
| 2 per year | – | – | 10.1 (8.6 to 11.7) min | 11.6 (10.3 to 12.9) min | |
| 1 per year | – | – | 16.0 (14.2 to 17.7) min | 24.0 (22.3 to 25.7) min | |
| Onset of action | 30 min | Reference | Reference | – | – |
| 20 min | 1.1 (0.85 to 1.3) per year | 0.9 (0.7 to 1.0) per year | – | – | |
| 15 min | 1.8 (1.5 to 2.0) per year | 1.4 (1.2 to 1.5) per year | – | – | |
| 5 min | 3.1 (2.7 to 3.4) per year | 2.1 (1.9 to 2.2) per year | – | – | |
| 5-year risk of osteoporosis | 6% | Reference | Reference | Reference | Reference |
| 5% | 0.6 (0.4 to 0.8) per year | 0.4 (0.3 to 0.5) per year | 4.9 (3.5 to 6.4) min | 4.5 (3.4 to 5.7) min | |
| 4% | 1.3 (1.1 to 1.5) per year | 0.6 (0.5 to 0.7) per year | 10.8 (9.2 to 12.4) min | 7.1 (5.9 to 8.4) min | |
| Dosing frequency | Twice daily | Reference | Reference | Reference | Reference |
| Once daily | 0.4 (0.3 to 0.6) per year | 0.4 (0.3 to 0.5) per year | 3.6 (2.4 to 4.8) min | 4.6 (3.6 to 5.6) min | |
| Priming | New capsule each time | Reference | Reference | Reference | Reference |
| New canister+one step | 1.1 (0.9 to 1.4) per year | 0.6 (0.5 to 0.7) per year | 9.2 (7.4 to 11.0) min | 7.1 (5.7 to 8.4) min | |
| Discharge+one step | 1.05 (0.8 to 1.3) per year | 0.4 (0.2 to 0.5) per year | 8.5 (6.6 to 10.4) min | 4.4 (2.8 to 6.1) min | |
| One or two simple steps | 1.2 (0.9 to 1.4) per year | 0.6 (0.5 to 0.7) per year | 9.4 (7.5 to 11.3) min | 7.2 (5.6 to 8.9) min | |
| Device type | Dry powder inhaler | Reference | Reference | Reference | Reference |
| Soft mist inhaler | 0.7 (0.5 to 0.9) per year | 0.1 (0.0 to 0.2) per year | 5.6 (4.1 to 7.1) min | 1.4 (0.2 to 2.6) min | |
| Pressurised inhaler | 1.0 (0.8 to 1.2) per year | 0.3 (0.2 to 0.4) per year | 8.1 (6.5 to 9.6) min | 3.6 (2.4 to 4.8) min | |
| Dose counter | Metered dose counter | Reference | Reference | Reference | Reference |
| Every 10 doses | 0.1 (−0.1 to 0.3) per year | −0.2 (−0.3 to −0.1) per year | 0.7 (−0.7 to 2.2) min | −3.0 (−4.2 to −1.8) min | |
| Every dose | 0.2 (0.1 to 0.4) per year | 0.1 (0.0 to 0.2) per year | 1.9 (0.4 to 3.4) min | 1.6 (0.3 to 2.8) min | |
| 5-year risk of pneumonia | 20% | – | Reference | – | Reference |
| 15% | – | 0.5 (0.4 to 0.6) per year | – | 6.0 (4.8 to 7.2) min | |
| 10% | – | 1.1 (1.0 to 1.2) per year | – | 13.5 (12.2 to 14.9) min | |
*How many additional exacerbations a respondent was willing to accept for each of the attribute levels, relative to their respective reference level (see online supplementary table 4 for calculations).
†How many extra minutes of onset of action patients were willing to accept for each of the attribute levels, relative to their respective reference level (see online supplementary table 5 for calculations).