Table 1.
Comparison of subjects’ sociodemographic characteristics.
| Characteristics | Total (N = 20,987) | Obese children (N = 1,386) | Normal (N = 12,020) | P value |
|---|---|---|---|---|
| Age, mean (SD) | 9.21 (1.74) | 8.92 (1.61) | 9.24 (1.75) | <0.001 |
| Male, n (%) | 6,377 (47.6%) | 1,042 (16.3%) | 5,335 (83.7%) | <0.001 |
| Female, n (%) | 7,029 (52.4%) | 344 (4.9%) | 6,685 (95.1%) | |
| NE, n (%) | 592 (4.4%) | 79 (5.8%) | 513 (4.3%) | 0.013 |
| Asthma, n (%) | 421 (3.1%) | 67 (4.8%) | 354 (2.9%) | <0.001 |
| ADHD, n (%) | 540 (4.0%) | 63 (4.6%) | 477 (4.0%) | 0.298 |
| Depressive feelings, n (%) | 2,149 (16.0%) | 272 (19.6%) | 1,877 (15.6%) | <0.001 |
| Snoring, n (%) | 1,572 (11.7%) | 287 (20.7%) | 1,285 (10.7) | <0.001 |
| Maternal educational level | 0.524 | |||
| Illiterate | 161 (1.2%) | 19 (1.4%) | 142 (1.2%) | |
| Primary or middle school | 3,438 (26.1%) | 367 (26.9%) | 3,071 (26.0%) | |
| Junior high school | 4,482 (34.0%) | 478 (35.1%) | 4,004 (33.9%) | |
| College or university | 4,329 (32.8%) | 420 (30.8%) | 3,909 (33.1%) | |
| Master or doctor’s degree | 772 (5.9%) | 79 (5.8%) | 693 (5.9%) | |
| Paternal educational level | 0.644 | |||
| Illiterate | 88 (0.7%) | 10 (0.7%) | 78 (0.7%) | |
| Primary or middle school | 2,958 (22.2%) | 316 (22.9%) | 2,642 (22.1%) | |
| Junior high school | 4,659 (34.9%) | 486 (35.3%) | 4,173 (34.9%) | |
| College or university | 4,269 (32.0%) | 441 (32.0%) | 3,828 (34.9%) | |
| Master or doctor’s degree | 1,362 (10.2%) | 125 (9.1%) | 1,237 (10.3%) | |
| House sizea | 0.895 | |||
| <15 | 1,911 (14.4%) | 195 (14.3%) | 1,716 (14.5%) | |
| 15–25 | 4,180 (31.6%) | 420 (30.8%) | 3,760 (31.7%) | |
| 25–35 | 3,397 (25.7%) | 359 (26.3%) | 3,038 (25.7%) | |
| >35 | 3,742 (28.3%) | 389 (28.5%) | 3,353 (28.3%) | |
| Family structure | 0.155 | |||
| Single-parent family | 697 (5.2%) | 69 (5.0%) | 628 (5.2%) | |
| Two-parent family | 8,501 (63.7%) | 853 (61.6%) | 7,648 (63.9%) | |
| Large family | 4,145 (31.1%) | 462 (33.4%) | 3,692 (30.8%) | |
| Household incomeb | 0.365 | |||
| <125 | 2,507 (18.9%) | 242 (17.6%) | 2,265 (19.0%) | |
| 125–235 | 4,426 (33.3%) | 449 (32.6%) | 3,977 (33.4%) | |
| 235–390 | 3,190 (24.0%) | 351 (25.5%) | 2,839 (23.8%) | |
| >390 | 3,162 (23.8%) | 335 (24.3%) | 2,827 (23.7%) | |
| Age group | <0.001 | |||
| 5–6 years old | 1,509 (11.3%) | 165 (11.9%) | 1,344 (11.2%) | |
| 7 years old* | 2,282(17.0%) | 291 (21.0%) | 1,991 (16.6%) | |
| 8 years old* | 2,415 (18.0%) | 278 (20.1%) | 2,137 (17.8%) | |
| 9 years old | 2,369(17.7%) | 269 (18.8%) | 2,100 (17.5%) | |
| 10 years old | 2,195 (16.4%) | 210 (15.2%) | 1,985 (16.5%) | |
| 11–12 years old* | 2,636 (19.7%) | 182 (13.1%) | 2,454 (20.4%) |
Abbreviations: NE, nocturnal enuresis; SD, standard deviation; ADHD, attention deficit/hyperactivity disorder. aMeasure of house size is square meters per person; bmeasure of household income is dollars per person per month. *P < 0.05.