Table 4.

Adjusted multivariate logistic regression analysis^# for assessing the association between the duration of weekend catch-up outdoor and myopia (N = 5467)

Weekend catch-up outdoor time	Myopia (OR (95% CI))	P value
Complete sample
Normal (n = 3288)	Reference
1 h < time ≤ 2 h (n = 1443)	0.947 (0.825, 1.086)	0.434
2 h < time ≤ 3 h (n = 497)	0.761 (0.646, 0.896)	0.001*
3 h < time ≤ 4 h (n = 192)	0.652 (0.519, 0.818)	< 0.001*
time > 4 h (n = 47)	0.626 (0.451, 0.870)	0.005*
Weekday outdoor time ≤ 0.5 h
Normal (n = 661)	Reference
1 h < time ≤ 2 h (n = 330)	1.261 (0.603, 2.636)	0.538
2 h < time ≤ 3 h (n = 117)	0.987 (0.463, 2.103)	0.972
3 h < time ≤ 4 h (n = 35)	0.556 (0.246, 1.259)	0.159
time > 4 h (n = 47)	0.933 (0.328, 2.650)	0.896
0.5 h < Weekday outdoor time ≤ 1 h
Normal (n = 1635)	Reference
1 h < time ≤ 2 h (n = 725)	0.795 (0.621, 1.016)	0.067
2 h < time ≤ 3 h (n = 194)	0.577 (0.439, 0.758)	< 0.001*
3 h < time ≤ 4 h (n = 157)	0.571 (0.389, 0.839)	0.004*
time > 4 h (n = 0)	-	-
1 h < Weekday outdoor time ≤ 2 h
Normal (n = 678)	Reference
1 h < time ≤ 2 h (n = 243)	0.829 (0.653, 1.052)	0.124
2 h < time ≤ 3 h (n = 186)	0.614 (0.446, 0.844)	0.003*
time > 3 h (n = 0)	-	-
2 h < Weekday outdoor time ≤ 3 h
Normal (n = 103)	Reference
1 h < time ≤ 2 h (n = 84)	1.713 (0.876, 3.352)	0.116
time > 2 h (n = 0)	-	-
Weekday outdoor time > 3 h
Normal (n = 211)	Reference
1 h < time ≤ 2 h (n = 61)	1.585 (0.971, 2.441)	0.088
time > 2 h (n = 0)	-	-

#: Data was analyzed using adjusted multivariate logistic regression analysis and covariates used in the adjusted model contained age, grade, sex, ethnicity, BMI, resident, parents’ myopia, number of bad writing habits, working/studying time per day, continuous working/studying time per day, and screen time per day

*: P < 0.05