Table 1 Characteristics of the full sample and prevalence of self-reported myopia.
Variables | Number of participants | Self-reported myopia cases | Self-reported myopia rates (%) | χ2 or χ2-trend | P value |
|---|---|---|---|---|---|
Age | 5302.51a | < 0.001 | |||
<= 12 years | 14,484 | 4,049 | 28.0 | ||
> 12 years | 15,704 | 10,977 | 69.9 | ||
Sex | 190.00a | < 0.001 | |||
Male | 16,897 | 7,816 | 46.3 | ||
Female | 13,291 | 7,210 | 54.2 | ||
Grade | 5958.23b | < 0.001 | |||
Primary | 13,420 | 3,431 | 25.6 | ||
Junior high | 8,232 | 5,137 | 62.4 | ||
Senior high | 8,536 | 6,458 | 75.7 | ||
Family income | 1127.34b | < 0.001 | |||
Low | 4,113 | 1,598 | 38.9 | ||
Middle | 20,395 | 10,494 | 51.5 | ||
High | 5,680 | 2,934 | 51.7 | ||
Father’s education | 52.49b | < 0.001 | |||
Junior high or below | 9,641 | 5,025 | 52.1 | ||
Senior high | 11,387 | 5,712 | 50.2 | ||
College or above | 9,160 | 4,289 | 46.8 | ||
Mother’s education | 119.86b | < 0.001 | |||
Junior high or below | 12,203 | 6,448 | 52.8 | ||
Senior high | 11,184 | 5,554 | 49.7 | ||
College or above | 68,01 | 3,024 | 44.5 | ||
Father myopia | 442.40a | < 0.001 | |||
Yes | 8,414 | 4,936 | 58.7 | ||
No | 20,791 | 9,503 | 45.7 | ||
Unknown | 983 | 587 | 59.7 | ||
Mother myopia | 290.62a | < 0.001 | |||
Yes | 8,696 | 4,955 | 57.0 | ||
No | 2,0524 | 9,525 | 46.4 | ||
Unknown | 968 | 546 | 56.4 | ||
Academic record | 148.18b | < 0.001 | |||
Bad | 7,580 | 3,494 | 46.1 | ||
Normal | 11,573 | 8,627 | 49.1 | ||
Good | 5,035 | 2,905 | 57.7 | ||
Academic workload | 397.40b | < 0.001 | |||
Light | 2,451 | 1,035 | 42.2 | ||
Normal | 19,020 | 8,847 | 46.5 | ||
Heavy | 8,717 | 5,144 | 59.0 | ||
Nighttime sleep duration | |||||
< 7 h/d | 13,354 | 9,162 | 68.6 | 3754.13b | < 0.001 |
7–8 h/d | 7,862 | 3,395 | 43.2 | ||
>= 8 h/d | 8,972 | 2,469 | 27.5 | ||
Daytime nap duration | 616.41a | < 0.001 | |||
None | 6,022 | 2,482 | 41.2 | ||
< 0.5 h/d | 9,229 | 5,542 | 60.0 | ||
>= 0.5 h/d | 14,937 | 7,002 | 46.9 | ||
Weekday bedtime | 198.59a | < 0.001 | |||
Regular | 19,585 | 9,164 | 46.8 | ||
Irregular | 10,603 | 5,862 | 55.3 | ||
Weekday wake time | 122.67a | < 0.001 | |||
Regular | 25,515 | 12,352 | 48.4 | ||
Irregular | 4,673 | 2,674 | 57.2 | ||
Weekend bedtime | 119.98b | < 0.001 | |||
Did not deviate | 6,263 | 2,945 | 47.0 | ||
Delayed < 1 h/d | 14,439 | 6,852 | 47.5 | ||
Delayed > = 1 h/d | 9,486 | 5,229 | 55.1 | ||
Weekend wake time | 309.10b | < 0.001 | |||
Did not deviate | 5,610 | 2,400 | 42.8 | ||
Delayed < 1 h/d | 11,793 | 5,519 | 46.8 | ||
Delayed > = 1 h/d | 12,,785 | 7,107 | 55.6 | ||
Sleep-wake time on weekdays | 235.61a | < 0.001 | |||
Regular | 18,526 | 8,572 | 46.3 | ||
Irregular | 11,662 | 6,454 | 55.3 | ||
Social jetlag | 125.46a | < 0.001 | |||
< 1 h | 12,088 | 5,540 | 39.0 | ||
>= 1 h | 18,100 | 9,486 | 50.9 |