Table 2.
Gender-specific quantile regression results for the different percentiles of BMI.
| Coefficienta (95% CI)b | |||||||
|---|---|---|---|---|---|---|---|
| 5th | 25th | 50th | 75th | 85th | 95th | 97th | |
| Boys | |||||||
| Model 1 | |||||||
| Intercept | 16.24 (15.54–16.94) | 18.12 (17.07–19.17) | 19.73 (19.37–20.09) | 20.97 (20.21–21.74) | 22.19 (21.41–22.98) | 23.36 (22.19–24.19) | 23.41 (22.55–24.27) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Age(years, centered at 13) | 0.48 (0.45–0.52) | 0.5 (0.48–0.53) | 0.51 (0.49–0.53) | 0.52 (0.49–0.55) | 0.54 (0.51–0.57) | 0.56 (0.51–0.61) | 0.58 (0.51–0.66) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Model 2 | |||||||
| Intercept | 16.16 (15.03–17.29) | 16.78 (15.53–18.02) | 19.92 (18.84–21.00) | 20.74 (20.23–21.26) | 21.49 (20.81–22.18) | 22.85 (22.03–23.67) | 22.90 (21.45–24.36) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Age(years, centered at 13) | 0.50 (0.47–0.54) | 0.51 (0.48–0.53) | 0.52 (0.49–0.55) | 0.53 (0.51–0.56) | 0.55 (0.52–0.57) | 0.51 (0.45–0.56) | 0.54 (0.48–0.60) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Cluster (moderate vs. low) | −0.69 (−2.00–0.61) | 1.30 (−0.55–3.15) | −0.68 (−1.85–0.50) | −0.29 (−0.91–0.31) | −0.67 (−2.18–0.83) | 1.08 (−0.38–2.54) | 1.07 (−0.95–3.09) |
| P values | 0.29 | 0.17 | 0.26 | 0.34 | 0.37 | 0.15 | 0.29 |
| Cluster (high vs. low) | 0.70 (−0.67–2.07) | 1.30 (−0.09–2.69) | 0.04 (−1.58–1.67) | 1.82 (0.17–3.48) | 1.78 (0.49–3.08) | 1.66 (0.20–3.13) | 1.20 (−1.04–3.43) |
| P values | 0.32 | 0.07 | 0.96 | 0.03 | 0.007 | 0.03 | 0.29 |
| Girls | |||||||
| Model 1 | |||||||
| Intercept | 16.21 (15.72–16.69) | 18.03 (17.19–18.87) | 19.60 (19.16–20.03) | 21.13 (20.76–21.51) | 21.64 (21.11–22.17) | 22.71 (21.45–23.98) | 22.81 (20.55–25.07) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Age(years, centered at 13) | 0.40 (0.36–0.44) | 0.41 (0.38–0.44) | 0.40 (0.38–0.43) | 0.40 (0.37–0.43) | 0.40 (0.37–0.43) | 0.41 (0.35–0.46) | 0.41(0.34–0.47) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Model 2 | |||||||
| Intercept | 16.13 (15.33–16.91) | 17.47 (16.58–18.36) | 19.10 (18.29–19.70) | 20.72 (19.59–21.84) | 21.40 (20.28–22.53) | 22.78 (21.54–24.03) | 22.90 (21.64–24.16) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Age(years, centered at 13) | 0.41 (0.37–0.45) | 0.39 (0.37–0.41) | 0.40 (0.37–0.42) | 0.40 (0.37–0.43) | 0.39 (0.36–0.43) | 0.36 (0.31–0.41) | 0.37 (0.31–0.43) |
| P values | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Cluster (moderate vs. low) | −0.22 (−1.20–0.75) | −0.35 (−1.39–0.68) | −0.44 (−1.73–0.85) | −0.16 (−1.75–1.43) | 0.26 (−1.04–1.55) | −0.08 (−1.49–1.33) | 0.05(−1.60–1.71) |
| P values | 0.65 | 0.50 | 0.50 | 0.84 | 0.70 | 0.91 | 0.95 |
| Cluster (high vs. low) | 0.57 (−0.76–1.90) | 1.45 (0.49–2.43) | 1.05 (0.21–1.88) | 0.64 (−0.73–2.02) | 0.94 (−0.57–2.46) | 2.31 (0.40–4.23) | 2.44 (0.72–4.15) |
| P values | 0.40 | 0.003 | 0.015 | 0.36 | 0.22 | 0.018 | 0.006 |
BMI = Body Mass Index, CI: confidence interval.
aThe coefficient represents the difference in the value of BMI at the nth percentile for moderate- and high-risk parental clusters compare to low-risk. For age the coefficient represents the change in the value of BMI at the nth percentile for one year increase in age. The intercept is the value of the nth percentile of BMI when all variables are zero.
bConfidence intervals (CI) are based on 100 bootstrap samples.
P values were obtained using longitudinal quantile regression analysis.