Psychometric Properties of the ABCC Scale for People With Asthma (n = 62)
| Convergent validity, AQLQ-S, r | ||||
|---|---|---|---|---|
| ABCC domains | Total | Symptoms | Activity Limitation | Emotional Function |
| ABCC total | −0.851a | −0.842a | −0.831a | … |
| Feelings and emotions | … | … | … | −0.725a |
| Physical limitation | −0.777a | −0.782a | −0.797a | … |
| Asthma complaints | −0.835a | −0.865a | −0.805a | … |
| Known group validity, median (IQR) | |||
|---|---|---|---|
| No Exacerbations (n = 16) | ≥1 Exacerbations (n = 46) | P value | |
| ABCC total | 1.5 (0.9-1.9) | 2.5 (1.8-3.1) | <.001 |
| Night’s rest | 2.0 (1.0-2.0) | 3.0 (2.0-4.0) | .001 |
| Feelings and emotions | 1.0 (0.8-1.3) | 1.3 (0.6-2.0) | .049 |
| Physical limitations | 1.7 (0.7-2.0) | 2.3 (1.7-3.3) | <.001 |
| Relations and work | 1.0 (0.0-2.0) | 3.0 (2.0-4.0) | .001 |
| Asthma complaints | 0.8 (0.5-1.6) | 3.0 (2.0-3.8) | <.001 |
| Controlledb (n = 18) | Uncontrolledb (n =43) | P value | |
| ABCC total | 1.4 (1.0-1.8) | 2.7 (2.0-3.2) | <.001 |
| Night’s rest | 2.0 (1.0-3.0) | 3.0 (2.0-4.0) | 0.003 |
| Feelings/emotions | 0.5 (0.0-1.0) | 1.3 (1.0-2.0) | <.001 |
| Physical limitations | 1.0 (0.7-2.0) | 2.3 (1.7-3.3) | <.001 |
| Relations and work | 1.0 (0.0-2.0) | 3.0 (2.0-4.0) | <.001 |
| Sexuality | 0.5 (0.0-2.0) | 2.0 (0.0-3.0) | .042 |
| Asthma complaints | 0.8 (0.2-1.5) | 3.0 (2.3-3.8) | <.001 |
| Reliability measures | |
|---|---|
| Internal consistency, Cronbach’s α (95% CI) | |
| Total scale | 0.92 (0.89-0.95) |
| Physical limitations | 0.88 (0.82-0.93) |
| Feelings and emotions | 0.74 (0.60-0.83) |
| Asthma complaints | 0.73 (0.61-0.83) |
| Test-retest reliability, ICC (95% CI) (n = 60) | |
| 0.93 (0.87-0.96) | |
ABCC = Assessment of Burden of Chronic Conditions; AQLQ-S = Standardized Asthma Quality of Life Questionnaire; ICC = intraclass coefficient; IQR = interquartile range; GINA = Global Initiative for Asthma; r = Pearson correlation coefficient.
↵a r < −0.7.
↵b Groups determined by GINA guidelines. Well and partially controlled combined into single group.