01.12.2017 | Research article | Ausgabe 1/2017 Open Access

Near work, outdoor activity, and myopia in children in rural China: the Handan offspring myopia study
- Zeitschrift:
- BMC Ophthalmology > Ausgabe 1/2017
Electronic supplementary material
Background
Methods
Questionnaire
Cycloplegic refraction
Data analysis and definitions
Results
Included (
N = 572)
|
Excluded (
N = 306)
|
P
|
|
---|---|---|---|
Age (years)
|
10.6 ± 2.5
|
10.5 ± 2.5
|
0.44
|
Gender (boys:girls)
|
316:256
|
146:160
|
0.03
|
Prevalence of myopia (%)
a
|
|||
Boys
|
17.1
|
17.2
|
0.86
|
Girls
|
32.8
|
27.3
|
0.12
|
Total
|
24.1
|
22.6
|
0.65
|
Spherical equivalent (D)
a
|
|||
Boys
|
0.15 ± 1.18
|
0.19 ± 1.44
|
0.81
|
Girls
|
−0.17 ± 1.27
|
−0.24 ± 1.75
|
0.65
|
Total
|
0.01 ± 1.23
|
−0.05 ± 1.63
|
0.63
|
N
|
Near work
|
Outdoor
|
|||
---|---|---|---|---|---|
Mean ± SD
|
p value
|
Mean ± SD
|
p value
|
||
Gender
|
|||||
Boys
|
316
|
4.9 ± 1.7
|
0.042
a
|
3.0 ± 1.4
|
0.12
a
|
Girls
|
256
|
4.6 ± 1.5
|
2.8 ± 1.4
|
||
Refractive Status
|
|||||
Myopia
|
138
|
5.0 ± 1.7
|
0.049
a
|
2.9 ± 1.3
|
0.38
a
|
No myopia
|
434
|
4.7 ± 1.6
|
3.0 ± 1.4
|
||
Number of myopic parents
|
|||||
None
|
197
|
4.6 ± 1.7
|
0.32
b
|
2.9 ± 1.3
|
0.74
b
|
Either
|
272
|
4.9 ± 1.7
|
2.9 ± 1.4
|
||
Both
|
103
|
4.7 ± 1.4
|
3.0 ± 1.5
|
||
Maternal education levels
|
|||||
Illiteracy
|
87
|
4.7 ± 1.6
|
0.17
b
|
2.9 ± 1.2
|
0.054
b
|
Primary school
|
279
|
4.6 ± 1.7
|
2.8 ± 1.3
|
||
Junior high school
|
189
|
5.0 ± 1.5
|
3.2 ± 1.6
|
||
Senior high school and above
|
17
|
4.8 ± 1.6
|
3.1 ± 1.4
|
||
Paternal education levels
|
|||||
Illiteracy
|
21
|
5.4 ± 2.5
|
0.018
b
|
3.0 ± 1.1
|
0.38
b
|
Primary school
|
166
|
4.6 ± 1.6
|
2.8 ± 1.4
|
||
Junior high school
|
343
|
4.7 ± 1.5
|
3.0 ± 1.5
|
||
Senior high school and above
|
42
|
5.3 ± 2.1
|
2.8 ± 1.3
|
||
Total
|
572
|
4.8 ± 1.6
|
2.9 ± 1.4
|
Near work activity (hours per day)
b
|
Low (0~4.0)
N = 185
|
Moderate (4.0~5.1)
N = 196
|
High (>5.1)
N = 191
|
P value
|
---|---|---|---|---|
Gender
|
||||
Boys
|
0.33
|
0.08
|
0.06
|
0.17
|
Girls
|
−0.15
|
−0.19
|
−0.20
|
0.96
|
Refractive Status
|
||||
Myopia
|
−1.73
|
−1.74
|
−1.80
|
0.95
|
No myopia
|
0.63
|
0.52
|
0.53
|
0.25
|
Number of myopic parents
|
||||
None
|
0.09
|
−0.04
|
0.04
|
0.80
|
Either
|
0.30
|
0.04
|
0.01
|
0.17
|
Both
|
−0.29
|
−0.32
|
−0.46
|
0.89
|
Maternal education level
|
||||
Illiteracy
|
0.15
|
0.19
|
0.12
|
0.97
|
Primary school
|
−0.01
|
−0.01
|
0.00
|
0.99
|
Junior high school
|
0.39
c
|
−0.13
|
−0.04
|
0.06
|
Senior high school and above
|
−1.30
|
−0.68
|
−0.85
|
0.88
|
Paternal education level
|
||||
Illiteracy
|
0.08
|
0.27
|
0.53
|
0.50
|
Primary school
|
0.38
c
|
−0.11
|
−0.15
|
0.01
|
Junior high school
|
−0.06
|
−0.05
|
0.04
|
0.78
|
Senior high school and above
|
0.11
|
−0.01
|
−0.61
|
0.50
|
Total
|
0.10
|
−0.04
|
−0.06
|
0.35
|
Outdoor activity (hours per day)
b
|
Low (0~2.3)
N = 191
|
Moderate (2.3~3.2)
N = 187
|
High (>3.2)
N = 194
|
P value
|
---|---|---|---|---|
Gender
|
||||
Boys
|
0.05
|
0.10
|
0.27
|
0.32
|
Girls
|
−0.13
|
−0.30
|
−0.10
|
0.49
|
Refractive Status
|
||||
Myopia
|
−1.69
|
−1.76
|
−1.84
|
0.82
|
No myopia
|
0.54
|
0.53
|
0.61
|
0.52
|
Number of myopic parents
|
||||
None
|
0.03
|
−0.19
|
0.25
|
0.10
|
Either
|
0.08
|
−0.01
|
0.26
|
0.24
|
Both
|
−0.53
|
−0.09
|
−0.46
|
0.32
|
Maternal education level
|
||||
Illiteracy
|
0.16
|
−0.10
|
0.40
|
0.09
|
Primary school
|
−0.09
|
−0.05
|
0.14
|
0.37
|
Junior high school
|
0.01
|
−0.07
|
0.11
|
0.68
|
Senior high school and above
|
0.11
|
−0.94
|
−1.68
|
0.52
|
Paternal education level
|
||||
Illiteracy
|
−0.01
|
0.22
|
0.54
|
0.62
|
Primary school
|
0.07
|
−0.11
|
0.22
|
0.30
|
Junior high school
|
−0.06
|
−0.11
|
0.10
|
0.31
|
Senior high school and above
|
−0.27
|
−0.12
|
−0.25
|
0.97
|
Total
|
−0.04
|
−0.09
|
0.12
|
0.20
|
Near work
|
Outdoor
|
|||
---|---|---|---|---|
OR
|
95% CI
|
OR
|
95% CI
|
|
Model 1
|
1.12
|
1.01–1.25
|
0.93
|
0.82–1.07
|
Model 2
|
1.07
|
0.94–1.21
|
0.86
|
0.74–1.00
|
Model 3
|
1.05
|
0.92–1.21
|
0.86
|
0.75–1.00
|
Model 4
|
1.10
|
0.94–1.27
|
0.82
|
0.70–0.96
|