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 |
(a)Items ordered by factor analysis. (b)Test-retest reliability.
The numbers in bold refer to the highest factor loading for each item.