Table 2.
Score distribution characteristics of the five CHAQ versions.
| CHAQ Version | Median (range) | % at ceiling | KS-statistic | p | IQR | Skewness | Kurtosis |
|---|---|---|---|---|---|---|---|
| CHAQ30orig | 0.38 (0-2.13) | 27* | 0.19 | <0.001 | 1.06 | 0.85 | -0.51 |
| CHAQ30CATI | 0.10 (0-1.62)a, c | 27* | 0.22 | <0.001 | 0.40 | 1.62 | 2.65 |
| CHAQ38CATI | 0.19 (0-1.84)a, b | 14 | 0.19 | <0.001 | 0.49 | 1.42 | 1.69 |
| CHAQ30CATII | -0.033 (-1.69-2)e | 1 | 0.24 | <0.001 | 0.35 | 0.94 | 5.43 |
| CHAQ38CATII | -0.12 (-1.7-1.76)d | 0 | 0.20 | <0.001 | 0.45 | 0.72 | 3.60 |
* ceiling effect, > 15% at ceiling; IQR: Interquartile range, KS: Kolmogorov Smirnov; p: probability value of the KS one sample test of normality.
a significantly different from CHAQ30orig, Wilcoxon p < 0.001
b significantly different from CHAQ30CATI, Wilcoxon p < 0.001
c significantly different from CHAQ38CATI, Wilcoxon p < 0.001
d significantly different from CHAQ30CATII, Wilcoxon p < 0.001
e significantly different from CHAQ38CATII, Wilcoxon p < 0.001