Table 1.
Background characteristics of participants (N=3081).
| Characteristic | Value, n (%) | ||
| Sex | |||
|
|
Female | 1525 (49.49) | |
|
|
Male | 1550 (50.31) | |
|
|
Missing data | 6 (0.19) | |
| Grade | |||
|
|
Seven | 1979 (64.23) | |
|
|
Eight | 579 (18.79) | |
|
|
Nine | 523 (16.98) | |
| Study site | |||
|
|
Guangzhou | 1126 (36.55) | |
|
|
Chengdu | 1955 (63.45) | |
| Born in the city where the study was conducted | |||
|
|
Yes | 2367 (76.83) | |
|
|
No | 691 (22.43) | |
|
|
Missing data | 23 (0.75) | |
| Living with both parents | |||
|
|
Yes | 2382 (77.31) | |
|
|
No | 639 (20.74) | |
|
|
Missing data | 60 (1.95) | |
| Father’s educational level | |||
|
|
Junior middle school or below | 1489 (48.33) | |
|
|
Senior middle school or equal | 831 (26.97) | |
|
|
College or above | 594 (19.28) | |
|
|
Missing data | 167 (5.42) | |
| Mother’s educational level | |||
|
|
Junior middle school or below | 1532 (49.72) | |
|
|
Senior middle school or equal | 803 (26.06) | |
|
|
College or above | 566 (18.37) | |
|
|
Missing data | 180 (5.84) | |
| Household income level when compared with classmates | |||
|
|
Much higher/higher | 672 (21.81) | |
|
|
Moderate | 2002 (64.98) | |
|
|
Lower/much lower | 387 (12.56) | |
|
|
Missing data | 20 (0.65) | |
| Self-reported academic performance | |||
|
|
Above average | 1020 (33.11) | |
|
|
Average | 1348 (43.75) | |
|
|
Below average | 600 (19.47) | |
|
|
Missing data | 113 (3.67) | |