Table 4 Multivariate logistic analysis of the risk factors for presence of RA and CA

Mean corneal curvature (D)

< 0.001

1.24

< 0.001

1.286

1.239 − 1.334

Learning stages

 kindergarten

Reference

Reference

 Primary school

0.204

0.893

0.885

0.99

0.861 − 1.138

 Junior high school

< 0.001

1.973

< 0.001

1.828

1.493 − 2.238

Spherical power (D)

0.021

0.956

0.744

1.006

0.971 − 1.042

Gender

 Boy

Reference

Reference

 Girl

< 0.001

0.698

0.283

1.059

0.954 − 1.177

Homework time on weekdays (hour/day)

0.029

1.074

0.06

1.062

0.997 − 1.130

Outdoor activity time on weekends (hour/day)

0.013

0.929

0.444

0.983

0.940 − 1.027

Watching TV within two meters

 Almost none

Reference

Reference

 Sometimes

0.126

1.103

0.427

1.044

0.938 − 1.162

 Often

0.06

1.254

0.712

1.041

0.843 − 1.285

Homework time on weekends (hour/day)

0.666

1.01

0.808

0.995

0.955 − 1.037

Outdoor activity time on weekdays (hour/day)

0.971

1.002

0.815

1.01

0.926 − 1.103

Continuous near work for more than 30–40 min

 Almost none

Reference

Reference

-

 Sometimes

0.569

1.048

0.708

0.973

0.844 − 1.122

 Often

0.235

0.892

0.448

0.94

0.803 − 1.102

Birth weight(g)

0.841

1

0.398

1

1.000 − 1.000

Preterm birth

 No

Reference

Reference

 Yes

0.642

1.066

0.77

1.037

0.813 − 1.322

Paternal myopia

 No

Reference

Reference

 Yes

0.05

1.137

0.62

0.973

0.872 − 1.085

Maternal myopia

 No

Reference

Reference

 Yes

0.271

1.076

0.566

1.033

0.925 − 1.154