Table 1 Descriptive statistics of research samples by wave (Mean(SD), %)
Variables | 2016 | 2018 | 2020 | All | P value |
|---|---|---|---|---|---|
Childhood nutritional information | |||||
 WAZ | 0.08 (1.49) | 0.23 (1.43) | 0.28 (1.39) | 0.19 (1.45) | 0.000 |
 HAZ | − 0.58(2.33) | − 0.24 (2.23) | − 0.05 (2.18) | − 0.32 (2.26) | 0.000 |
 BAZ | 0.45 (2.00) | 0.38 (1.91) | 0.36 (1.80) | 0.44 (1.93) | 0.059 |
 Underweight | 7.3 | 5.4 | 4.5 | 5.9 | 0.005 |
 Stunting | 15.7 | 10.0 | 6.0 | 11.1 | 0.000 |
 Wasting | 21.0 | 20.7 | 23.0 | 20.7 | 0.083 |
 Overweight/obesity | 32.6 | 36.1 | 33.5 | 34.4 | |
Childhood demographic information | |||||
 Age (month) | 19.30 (10.51) | 18.53 (10.03) | 20.43 (10.64) | 19.29 (10.39) | 0.000 |
 Male | 52.7 | 53.1 | 51.9 | 52.6 | 0.812 |
 Birth weight (kg) | 3.26 (0.56) | 3.24 (0.52) | 3.23 (0.52) | 3.25 (0.54) | 0.295 |
 Gestational age (month) | 9.49 (0.64) | 9.47 (0.67) | 9.49 (0.82) | 9.47 (0.69) | 0.263 |
 Months of breastfeeding | 9.59 (5.89) | 8.97 (5.87) | 8.89 (6.34) | 9.30 (6.08) | 0.013 |
Paternal sociodemographic information | |||||
 Paternal age | 30.76 (5.51) | 31.21 (5.30) | 31.42 (4.79) | 31.08 (5.28) | 0.010 |
 Paternal height (m) | 1.71 (5.39) | 1.72 (5.87) | 1.72 (5.66) | 1.72 (5.70) | 0.137 |
 Paternal BMI | 23.33 (3.44) | 23.55 (3.42) | 23.73 (3.36) | 23.55 (3.41) | 0.095 |
 Paternal ISEI | 36.47 (15.44) | 35.42 (19.18) | 37.13 (18.67) | 36.26 (17.63) | 0.083 |
Maternal sociodemographic information | |||||
 Maternal age | 28.58 (5.16) | 29.10 (4.69) | 29.67 (4.59) | 29.04 (4.87) | 0.000 |
 Maternal height (m) | 1.60 (5.23) | 1.60 (5.45) | 1.60 (5.50) | 1.60 (5.40) | 0.340 |
 Maternal BMI | 21.94 (3.46) | 22.34 (3.48) | 22.39 (3.31) | 22.24 (3.43) | 0.007 |
 Maternal ISEI | 30.10 (21.32) | 37.44 (19.14) | 33.67 (22.78) | 33.39 (21.28) | 0.000 |
Parental educational attainment (Paternal, maternal) | |||||
 No formal education | 8.5, 11.0 | 3.9, 5.7 | 2.8, 4.0 | 5.3, 7.0 | 0.000, 0.000 |
 Primary school | 19.8, 18.3 | 13.2, 11.7 | 7.0, 6.0 | 14.1, 12.4 | |
 Middle school | 35.6, 36.3 | 35.7, 35.7 | 35.0, 33.7 | 35.5, 35.4 | |
 High school | 17.8, 17.1 | 20.9, 20.7 | 21.6, 21.4 | 20.0, 19.7 | |
 College or higher | 18.3, 17.3 | 26.3, 26.3 | 33.7, 34.9 | 25.2, 25.6 | |
Household information | |||||
 Rural residence | 54.5 | 50.4 | 47.3 | 51.2 | 0.001 |
 Family size | 5.61 (2.16) | 5.40 (2.11) | 5.31 (2.07) | 5.46 (2.12) | 0.000 |
 Average income-1st quartile | 28.3 | 25.9 | 23.4 | 26.2 | 0.006 |
 Average income-2nd quartile | 31.0 | 31.3 | 30.3 | 30.9 | |
 Average income-3rd quartile | 24.3 | 27.0 | 26.0 | 25.8 | |
 Average income-4th quartile | 16.3 | 15.9 | 20.3 | 17.1 | |
City-level information | |||||
 GDP per capita (10,000 yuan) | 4.90 (4.69) | 5.34 (4.77) | 5.45 (4.48) | 5.29 (4.55) | 0.538 |
 Urbanization rate | 53.18 (12.89) | 55.46 (13.16) | 60.57 (13.97) | 57.65 (13.01) | 0.008 |
 Medium-/high-risk region | 33.6 | 31.4 | 31.1 | 32.2 | 0.301 |