Variables | Model 1 for total | Model 2 for boys | Model 3 for girls | |||
AOR (95% CI) | P value | AOR (95% CI) | P value | AOR (95% CI) | P value | |
Child characteristics | ||||||
Gender (girl/boy (ref.)) | 1.21 (0.93 to 1.57) | 0.151 | — | — | — | — |
Age (8 years/7 years (ref.)) | 1.10 (0.81 to 1.50) | 0.533 | 0.96 (0.62 to 1.47) | 0.846 | 1.27 (0.81 to 2.00) | 0.305 |
Age (9 years/7 years (ref.)) | 1.84 (1.18 to 2.85) | 0.007 | 1.59 (0.84 to 3.00) | 0.156 | 2.18 (1.15 to 4.13) | 0.017 |
BMI (overweight/normal (ref.)) | 1.24 (0.84 to 1.82) | 0.284 | 1.49 (0.84 to 2.66) | 0.173 | 1.13 (0.66 to 1.92) | 0.667 |
BMI (obese/normal (ref.)) | 1.25 (0.90 to 1.72) | 0.177 | 1.35 (0.87 to 2.09) | 0.181 | 1.04 (0.63 to 1.70) | 0.883 |
Preterm birth (yes/no (ref.)) | 0.97 (0.59 to 1.62) | 0.919 | 1.27 (0.62 to 2.58) | 0.513 | 0.78 (0.37 to 1.64) | 0.504 |
Parental characteristics | ||||||
Family education level (college or more/high school or less (ref.)) | 0.86 (0.55 to 1.34) | 0.496 | 0.75 (0.41 to 1.37) | 0.348 | 1.10 (0.56 to 2.16) | 0.782 |
Monthly household income (yuan)(≥10 001/<10 001 (ref.)) | 0.66 (0.48 to 0.89) | 0.008 | 0.68 (0.43 to 1.07) | 0.093 | 0.59 (0.38 to 0.92) | 0.020 |
Parental myopia (one myopia/none (ref.)) | 2.92 (1.93 to 4.42) | <0.001 | 3.33 (1.85 to 5.98) | <0.001 | 2.42 (1.33 to 4.38) | 0.004 |
Parental myopia (both myopia/none (ref.)) | 5.66 (3.71 to 8.63) | <0.001 | 6.05 (3.32 to 11.03) | <0.001 | 5.04 (2.75 to 9.26) | <0.001 |
Time for outdoor activity and near screen (hours per day) | ||||||
Outdoor activity (≥2.0/<2.0 (ref.)) | 0.97 (0.74 to 1.28) | 0.843 | 0.91 (0.62 to 1.35) | 0.653 | 1.00 (0.67 to 1.49) | 0.994 |
Near screen (≥1.0/<1.0 (ref.)) | 1.16 (0.87 to 1.54) | 0.312 | 1.33 (0.89 to 1.99) | 0.170 | 1.01 (0.67 to 1.53) | 0.957 |
Eye habits | ||||||
Reading books too close (yes/no (ref.)) | 1.58 (1.20 to 2.08) | 0.001 | 1.08 (0.73 to 1.58) | 0.711 | 2.45 (1.62 to 3.69) | <0.001 |
Watching a screen too close (yes/no (ref.)) | 1.24 (0.95 to 1.62) | 0.121 | 1.67 (1.13 to 2.47) | 0.010 | 0.92 (0.62 to 1.36) | 0.668 |
Writing with a tilted head (yes/no (ref.)) | 1.37 (1.05 to 1.77) | 0.019 | 1.69 (1.16 to 2.47) | 0.006 | 1.16 (0.80 to 1.69) | 0.424 |
Reading while lying down (yes/no (ref.)) | 0.68 (0.48 to 0.98) | 0.037 | 0.68 (0.42 to 1.12) | 0.133 | 0.65 (0.38 to 1.10) | 0.109 |
Sleep status | ||||||
Sleep patterns (LE/EE (ref.)) | 1.33 (0.85 to 2.10) | 0.215 | 1.23 (0.61 to 2.49) | 0.564 | 1.45 (0.78 to 2.68) | 0.241 |
Sleep patterns (EL/EE (ref.)) | 1.52 (1.02 to 2.26) | 0.039 | 1.74 (0.98 to 3.12) | 0.060 | 1.47 (0.83 to 2.58) | 0.185 |
Sleep patterns (LL/EE (ref.)) | 1.40 (0.97 to 2.02) | 0.075 | 1.92 (1.11 to 3.33) | 0.020 | 1.08 (0.65 to 1.80) | 0.777 |
Sleep duration (hours) (≥9.0/<9.0 (ref.)) | 1.30 (0.91 to 1.85) | 0.147 | 1.19 (0.72 to 1.98) | 0.503 | 1.46 (0.88 to 2.41) | 0.141 |
Model 1 included child characteristics, parental characteristics, outdoor activity time, near screen (ie, mobiles, tablets, televisions and computers) time, eye habits and sleep status. Model 2 for boys and model 3 for girls include all variables in model 1 except gender.
Bold font data indicate p<0.05.
AOR, adjusted OR; BMI, body mass index; EE, early to bed early to rise; EL, early to bed late to rise; LE, late to bed early to rise; LL, late to bed late to rise.