Effect of treatment (ABC tool) on the total score and subdomains of the SGRQ at different points in time, as established with mixed linear regression correcting for age, gender, healthcare setting and smoking status, n=334
| Observed score, mean (SD) | β* | 95% CI | p Value | |||
|---|---|---|---|---|---|---|
| Intervention group | Control group | Lower | Upper | |||
| SGRQ symptoms | ||||||
| 6 months | 48.81 (22.83) | 43.15 (26.19) | −0.83 | −3.95 | 2.30 | 0.602 |
| 12 months | 44.65 (21.58) | 45.63 (26.27) | −5.50 | −8.92 | −2.07 | 0.002 |
| 18 months | 46.16 (23.69) | 45.33 (26.46) | −4.52 | −8.15 | −0.89 | 0.015 |
| SGRQ activity | ||||||
| 6 months | 45.35 (24.54) | 43.36 (25.96) | −0.86 | −3.74 | 2.02 | 0.557 |
| 12 months | 44.66 (24.92) | 43.62 (26.86) | −1.12 | −4.00 | 1.77 | 0.447 |
| 18 months | 44.23 (26.59) | 43.72 (27.45) | −2.34 | −5.52 | 0.83 | 0.147 |
| SGRQ impact | ||||||
| 6 months | 25.45 (16.24) | 23.14 (15.92) | 0.23 | −1.82 | 2.29 | 0.822 |
| 12 months | 24.43 (15.94) | 24.51 (15.59) | −1.46 | −3.42 | 0.50 | 0.144 |
| 18 months | 23.86 (15.58) | 24.68 (17.36) | −2.59 | −4.66 | −0.52 | 0.014 |
| SGRQ total score | ||||||
| 6 months | 39.88 (19.09) | 36.79 (20.29) | −0.90 | −2.85 | 1.05 | 0.365 |
| 12 months | 37.91 (18.33) | 38.10 (20.80) | −2.96 | −4.99 | −0.93 | 0.004 |
| 18 months | 38.39 (19.26) | 37.84 (21.92) | −3.08 | −5.36 | −0.80 | 0.008 |
*β=mixed linear regression weight for treatment at that point in time. β<0 indicates a lower score in the intervention group. Lower scores or negative change scores indicate a higher quality of life based on the SGRQ. Effects in this table are based on the mixed model after deleting the treatment effect at baseline, which was never significant. Effects before deleting the treatment effect were very similar and agreed with the present table in terms of significance yes/no.
ABC tool, Assessment of Burden of COPD tool; SGRQ, St. George's Respiratory Questionnaire.