Table 1 Minimal Clinically Important Difference (MCID) for the Clinical COPD Questionnaire (CCQ) by patient referencing. Differences between CCQ scores for Days 1 and 2 grouped according to Global Rating of Change (GRC) as scored by patients on a scale of -7 to 7. Note that paired-sample t-tests were used for total CCQ scores and for symptom and functional domains; Wilcoxon signed rank test was used for the mental domain.
CCQ score category | Score difference: Day 1 minus Day 2 | ||
|---|---|---|---|
Mean ± SD | 95% confidence interval | p value | |
GRC +1 (n = 3) | |||
Total | 0.30 ± 0.30 | -0.45, 1.05 | 0.225 |
Symptoms | -0.25 ± 1.64 | -4.32, 3.82 | 0.816 |
Function | 1.17 ± 0.80 | -0.83, 3.16 | 0.128 |
Mental | -0.5§ | 0.157 | |
GRC +2 to +3 (n = 15) | |||
Total | 0.40 ± 0.90 | -0.09, 0.91 | 0.098 |
Symptoms | 0.70 ± 1.09 | 0.98, 1.30 | 0.026* |
Function | 0.17 ± 1.37 | -0.93, 0.59 | 0.645 |
Mental | 1.0§ | 0.007* | |
GRC +4 to +5 (n = 14) | |||
Total | 1.31 ± 1.09 | 0.69, 1.94 | 0.001* |
Symptoms | 1.13 ± 1.52 | 0.25, 2.0 | 0.016* |
Function | 1.48 ± 1.25 | 0.76, 2.20 | 0.001* |
Mental | 0.5§ | 0.018* | |
GRC +6 to +7 (n = 2) | |||
Total | 1.95 ± 0.07 | 1.31, 2.59 | 0.016* |
Symptoms | 2.75 ± 1.77 | -13.13, 18.63 | 0.272 |
Function | 1.50 ± 1.06 | -8.03, 11.03 | 0.295 |
Mental | 1.25§ | 0.317 | |