Table 3

Maximum acceptable exacerbations and maximal acceptable onset time by disease

AttributeLevelMaximum acceptable exacerbationsMaximum acceptable onset time
Mean (95% CI)*Mean (95% CI)†
Asthma (n=810)COPD (n=1147)Asthma (n=810)COPD (n=1147)
Number of exacerbations3 per yearReferenceReference
2 per year10.1 (8.6 to 11.7) min11.6 (10.3 to 12.9) min
1 per year16.0 (14.2 to 17.7) min24.0 (22.3 to 25.7) min
Onset of action30 minReferenceReference
20 min1.1 (0.85 to 1.3) per year0.9 (0.7 to 1.0) per year
15 min1.8 (1.5 to 2.0) per year1.4 (1.2 to 1.5) per year
5 min3.1 (2.7 to 3.4) per year2.1 (1.9 to 2.2) per year
5-year risk of osteoporosis6%ReferenceReferenceReferenceReference
5%0.6 (0.4 to 0.8) per year0.4 (0.3 to 0.5) per year4.9 (3.5 to 6.4) min4.5 (3.4 to 5.7) min
4%1.3 (1.1 to 1.5) per year0.6 (0.5 to 0.7) per year10.8 (9.2 to 12.4) min7.1 (5.9 to 8.4) min
Dosing frequencyTwice dailyReferenceReferenceReferenceReference
Once daily0.4 (0.3 to 0.6) per year0.4 (0.3 to 0.5) per year3.6 (2.4 to 4.8) min4.6 (3.6 to 5.6) min
PrimingNew capsule each timeReferenceReferenceReferenceReference
New canister+one step1.1 (0.9 to 1.4) per year0.6 (0.5 to 0.7) per year9.2 (7.4 to 11.0) min7.1 (5.7 to 8.4) min
Discharge+one step1.05 (0.8 to 1.3) per year0.4 (0.2 to 0.5) per year8.5 (6.6 to 10.4) min4.4 (2.8 to 6.1) min
One or two simple steps1.2 (0.9 to 1.4) per year0.6 (0.5 to 0.7) per year9.4 (7.5 to 11.3) min7.2 (5.6 to 8.9) min
Device typeDry powder inhalerReferenceReferenceReferenceReference
Soft mist inhaler0.7 (0.5 to 0.9) per year0.1 (0.0 to 0.2) per year5.6 (4.1 to 7.1) min1.4 (0.2 to 2.6) min
Pressurised inhaler1.0 (0.8 to 1.2) per year0.3 (0.2 to 0.4) per year8.1 (6.5 to 9.6) min3.6 (2.4 to 4.8) min
Dose counterMetered dose counterReferenceReferenceReferenceReference
Every 10 doses0.1 (−0.1 to 0.3) per year−0.2 (−0.3 to −0.1) per year0.7 (−0.7 to 2.2) min−3.0 (−4.2 to −1.8) min
Every dose0.2 (0.1 to 0.4) per year0.1 (0.0 to 0.2) per year1.9 (0.4 to 3.4) min1.6 (0.3 to 2.8) min
5-year risk of pneumonia20%ReferenceReference
15%0.5 (0.4 to 0.6) per year6.0 (4.8 to 7.2) min
10%1.1 (1.0 to 1.2) per year13.5 (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).