Table 1.
Comparisons of variables in training and validation sets
| Variable | Total (n=1,412) | Training set (n=988) | Validation set (n=424) | Χ2 | P |
|---|---|---|---|---|---|
| Group | 5.434 | 0.143 | |||
| Normal | 915 (64.8) | 638 (64.57) | 277 (65.33) | ||
| Stunting | 167 (11.83) | 113 (11.44) | 54 (12.74) | ||
| Underweight | 164 (11.61) | 109 (11.03) | 55 (12.97) | ||
| Wasting | 166 (11.76) | 128 (12.96) | 38 (8.96) | ||
| Age | 3.936 | 0.140 | |||
| 8 years | 454 (32.15) | 313 (31.68) | 141 (33.25) | ||
| 9 years | 469 (33.22) | 317 (32.09) | 152 (35.85) | ||
| 10 years | 489 (34.63) | 358 (36.23) | 131 (30.90) | ||
| Sex | 0.014 | 0.907 | |||
| Male | 726 (51.42) | 509 (51.52) | 217 (51.18) | ||
| Female | 686 (48.58) | 479 (48.48) | 207 (48.82) | ||
| Gestational Age | 0.136 | 0.712 | |||
| ≥37 weeks | 1226 (86.83) | 879 (88.97) | 347 (81.84) | ||
| <37 weeks | 186 (13.17) | 109 (11.03) | 77 (18.16) | ||
| Birth Weight | 0.294 | 0.588 | |||
| ≥2.5 kg | 1,096 (77.62) | 763 (77.23) | 333 (78.54) | ||
| <2.5 kg | 316 (22.38) | 225 (22.77) | 91 (21.46) | ||
| Residence | 0.146 | 0.702 | |||
| Rural | 667 (47.24) | 470 (47.57) | 197 (46.46) | ||
| Urban | 745 (52.76) | 518 (52.43) | 227 (53.54) | ||
| Left Behind Children | 2.364 | 0.124 | |||
| No | 983 (69.62) | 700 (70.85) | 283 (66.75) | ||
| Yes | 429 (30.38) | 288 (29.15) | 141 (33.25) | ||
| Household income | 0.092 | 0.761 | |||
| <100 thousand yuan | 558 (39.52) | 393 (39.78) | 165 (38.92) | ||
| ≥100 thousand yuan | 854 (60.48) | 595 (60.22) | 259 (61.08) | ||
| Number of children | 0.039 | 0.843 | |||
| >1 | 677 (47.95) | 472 (47.77) | 205 (48.35) | ||
| 1 | 735 (52.05) | 516 (52.23) | 219 (51.65) | ||
| Sleep Duration | 0.065 | 0.799 | |||
| ≥9 hours | 802 (56.80) | 559 (56.58) | 243 (57.31) | ||
| <9 hours | 610 (43.20) | 429 (43.42) | 181 (42.69) | ||
| Parents education level | 0.099 | 0.753 | |||
| Low level | 735 (52.05) | 517 (52.33) | 218 (51.42) | ||
| High level | 677 (47.95) | 471 (47.67) | 206 (48.58) | ||
| Bad eating habits | 0.193 | 0.66 | |||
| No | 897 (63.53) | 624 (63.16) | 273 (64.39) | ||
| Yes | 515 (36.47) | 364 (36.84) | 151 (35.61) | ||
| Calcium Deficiency | 0.045 | 0.831 | |||
| No | 1,190 (84.28) | 834 (84.41) | 356 (83.96) | ||
| Yes | 222 (15.72) | 154 (15.59) | 68 (16.04) | ||
| Iron Deficiency | 8.249 | 0.004 | |||
| No | 1,183 (83.78) | 846 (85.63) | 337 (79.48) | ||
| Yes | 229 (16.22) | 142 (14.37) | 87 (20.52) | ||
| Zinc Deficiency | 0.019 | 0.890 | |||
| No | 1,324 (93.77) | 927 (93.83) | 397 (93.63) | ||
| Yes | 88 (6.23) | 61 (6.17) | 27 (6.37) | ||
| Mood disorders | 0.002 | 0.966 | |||
| No | 1,223 (86.61) | 856 (86.64) | 367 (86.56) | ||
| Yes | 189 (13.39) | 132 (13.36) | 57 (13.44) | ||
| Milk Intake | 2.747 | 0.097 | |||
| <300 ml/d | 895 (63.39) | 640 (64.78) | 255 (60.14) | ||
| ≥300 ml/d | 517 (36.61) | 348 (35.22) | 169 (39.86) | ||
| Physical activity time | 1.167 | 0.28 | |||
| ≥2 hours/d | 717 (50.78) | 511 (51.72) | 206 (48.58) | ||
| <2 hours/d | 695 (49.22) | 477 (48.28) | 218 (51.42) |
Notes: Parental education levels: high level, have completed ≥ nine years of compulsory education; low level, have not completed nine years of compulsory education.