Table 1. Socio-demographic and parental migration characteristics of the participants.
| All (%) | Boys (%) | Girls (%) | |
| Socio-demographic indicators | (n = 2558) | (n = 1407) | (n = 1151) |
| Grade | |||
| 7 | 44.5 | 42.6 | 46.9 |
| 8 | 33.0 | 34.7 | 30.8 |
| 9 | 22.5 | 22.7 | 22.2 |
| Age a (years, Mean, SD) | 13.8 (1.14) | 13.9 (1.15) | 13.6 (1.11) |
| Ethnicity | |||
| Han | 99.1 | 99.3 | 98.9 |
| Others | 0.9 | 0.7 | 1.1 |
| Guardian | |||
| Father | 56.7 | 61.8* | 50.7* |
| Mother | 35.9 | 31.2* | 41.4* |
| Grandparent | 3.0 | 2.1* | 4.1* |
| Others | 4.3 | 4.8* | 3.8* |
| Education level of guardian | |||
| Primary and low | 44.9 | 41.6* | 48.9* |
| Junior Secondary | 41.6 | 42.6* | 40.3* |
| Senior Secondary and above | 13.5 | 15.8* | 10.8* |
| Perceived living standard | |||
| Low (≤50%) | 62.9 | 66.1* | 59.1* |
| High (>50%) | 37.1 | 33.9* | 40.9* |
| Parental migration status | (n = 2558) | (n = 1407) | (n = 1151) |
| Paternal migration status | |||
| No | 58.8 | 58.8 | 58.8 |
| Yes, ever | 30.2 | 29.8 | 30.7 |
| Yes, currently | 11.0 | 11.4 | 10.6 |
| Maternal migration status | |||
| No | 85.5 | 82.9* | 88.6* |
| Yes, ever | 10.6 | 12.2* | 8.6* |
| Yes, currently | 3.9 | 4.9* | 2.8* |
| Type of parental migrationb | |||
| No parent migrating | 56.0 | 54.6* | 57.6* |
| Father migrating only | 29.9 | 28.6* | 31.4* |
| Mother migrating only | 3.4 | 4.2* | 2.3* |
| Both migrating | 10.8 | 12.6* | 8.7* |
| Paternal migration characteristics c | (n = 909) | (n = 496) | (n = 413) |
| Cumulative migration time | |||
| <3 years | 57.4 | 57.1 | 57.9 |
| ≥3 years | 42.6 | 42.9 | 42.1 |
| Frequency of returning home | |||
| ≥ Once per month | 39.8 | 41.6 | 37.8 |
| < Once per month | 60.1 | 58.4 | 62.2 |
| Frequency of contact with child | |||
| ≥ Once per month | 66.0 | 65.1 | 67.1 |
| < Once per month | 34.0 | 34.9 | 32.9 |
| Maternal migration characteristics d | (n = 311) | (n = 197) | (n = 114) |
| Cumulative migration time | |||
| <3 years | 62.1 | 64.5 | 57.9 |
| ≥3 years | 37.9 | 35.5 | 42.1 |
| Frequency of returning home | |||
| ≥ Once per month | 62.4 | 67.2* | 54.1* |
| < Once per month | 37.6 | 32.8* | 45.9* |
| Frequency of contact with child | |||
| ≥ Once per month | 69.2 | 70.7 | 66.3 |
| < Once per month | 30.8 | 29.3 | 33.7 |
a
The range of age was 11–19 years old.
b
Ever and current migration status were combined when creating the variable of ‘type of parental migration’.
c
Among participants with paternal migration only.
d
Among participants with maternal migration only.
*
Significant difference (P<0.05) between boys and girls by chi-square test.