Table 2.
Mean difference, Pearson correlation coefficient, intra-class correlation coefficient, and kappa coefficient for reported and measured height, weight, and body mass index (BMI)
| |
Measured minus self-reported values |
Pearson correlation coefficient |
Intra-class correlation coefficient and 95% CI |
Non-weighted kappa coefficient (SE) for categorised BMI |
Regression equation of reported in terms of measured data:regression coefficient and 95% CI |
||||
|---|---|---|---|---|---|---|---|---|---|
| Mean (SD) | <0 (%) | Zero (%) | >0(%) | Slope | Constant term | ||||
| Boys (N = 708) | |||||||||
| Height (m) |
0.0069 (0.33) |
28.8 |
24.6 |
46.6 |
0.96 |
0.92 (0.89-0.95) |
- |
1.00 (0.98-1.02) |
−0.01 (−0.045-0.025) |
| Weight (kg) |
1.03 (2.63) |
21.5 |
11.9 |
66.7 |
0.98 |
0.96 (0.95-0.97) |
- |
0.96 (0.94-0.97) |
1.06 (0.25-1.88) |
| BMI (kg/m2) |
0.22 (1.21) |
32.8 |
6.6 |
60.6 |
0.92 |
0.90 (0.84-0.96) |
0.66 (0.027) |
0.90 (0.87-0.93) |
1.72 (1.16-2.28) |
| Girls (N = 693) | |||||||||
| Height (m) |
0.0016 (0.023) |
33.3 |
28.4 |
38.2 |
0.96 |
0.93 (0.89-0.96) |
- |
1.03 (1.01-1.05) |
−0.045 (−0.079- -0.011) |
| Weight (kg) |
0.81 (2.22) |
23.5 |
11.4 |
65.1 |
0.98 |
0.96 (0.95-0.97) |
- |
0.97 (0.96-0.99) |
0.61 (−0.19-1.41) |
| BMI (kg/m2) |
0.29 (1.12) |
31.8 |
5.5 |
62.8 |
0.94 |
0.88 (0.83-0.93) |
0.75 (0.029) |
0.93 (0.90-0.95) |
1.18 (0.66-1.69) |
| Total sample (N = 1401) | |||||||||
| Height (m) |
0.0043 (0.29) |
31.0 |
26.5 |
42.5 |
0.96 |
0.96 (0.95-0.96) |
- |
1.01(0.99-1.02) |
−0.014 (−0.038-0.011) |
| Weight (kg) |
0.92 (2.44) |
22.5 |
11.6 |
65.9 |
0.98 |
0.92 (0.89-0.95) |
- |
0.96 (0.95-0.97) |
0.92 (0.35-1.49) |
| BMI (kg/m2) | 0.25 (1.17) | 32.3 | 6.1 | 61.7 | 0.93 | 0.88 (0.85-0.91) | 0.70 (0.020) | 0.91 (0.89-0.93) | 1.44 (1.06-1.83) |
N: number of subjects.
Bold type: mean value significantly different from zero, slope significantly different from 1, and constant term significantly different from zero (p < 0.05).