Grade | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|
Indoor studying (hours) | <0.5 | 0.5 to 1 | 1 to 2 | 2 to 3 | 3< |
Television viewing (hours) | <0.5 | 0.5 to 1 | 1 to 2 | 2 to 3 | 3< |
Screen time (hours) | <0.5 | 0.5 to 1 | 1 to 2 | 2 to 3 | 3< |
Outdoor activities (hours) | <0.5 | 0.5 to 1 | 1 to 2 | 2 to 3 | 3< |
Bedtime (time) | Before 21:00 | 21:00–22:00 | 22:00–23:00 | 23:00–24:00 | After 24:00 |
Dietary habit | Western | Moderately Western | Mixed | Modenately Japanese | Japanese |
Parental myopia | None | One | Both |