Table 1 Factor loadings after varimax rotation of the three components extracted and results of test-retest reliability for each DDQ item
DDQ items(a) | Factor 1–‘Eating and sleeping problems’ | Factor 2–‘Earache problems’ | Factor 3–‘Problems with brushing teeth’ | Weighted-kappa coefficient (95% Confidence Interval)(b) |
|---|---|---|---|---|
Cries during meals | 0.79 | -0.26 | -0.09 | 0.88 (0.74-1.00) |
Reaches for the cheek while eating | 0.77 | 0.24 | 0.06 | 0.75 (0.55-0.96) |
Puts away something nice to eat | 0.70 | 0.01 | 0.16 | 0.74 (0.52-0.96) |
Suddenly cries at night | 0.60 | 0.24 | 0.27 | 0.84 (0.69-0.98) |
Chews on one side | 0.59 | 0.28 | 0.17 | 0.97 (0.92-1.00) |
Has problems chewing | 0.53 | 0.20 | 0.36 | 0.77 (0.61-0.94) |
Bites with molars instead of front teeth | 0.47 | -0.08 | 0.30 | 0.68 (0.49-0.88) |
Has earache during the day | 0.04 | 0.86 | 0.07 | 0.80 (0.59-1.00) |
Has earache at night | 0.05 | 0.75 | 0.07 | 0.94 (0.84-1.00) |
Has earache during eating | 0.22 | 0.72 | 0.07 | 0.94 (0.83-1.00) |
Has problems with brushing lower teeth | 0.07 | 0.09 | 0.87 | 0.86 (0.71-1.00) |
Has problems with brushing upper teeth | 0.26 | 0.11 | 0.84 | 0.75 (0.57-0.93) |
Eigenvalues | 4.08 | 1.62 | 1.28 | |
% of variance | 34.04 | 13.52 | 10.67 | |
Cronbach’s alpha coefficient | 0.81 | 0.75 | 0.78 |