Table 2

Total outdoor activity by age, gender, race, father’s education, reading, IQ level, parental myopia and height

NOutdoorp Value
Mean (SD)
Age (years)<0.0001
    11–134542.59 (1.74)
    145283.54 (2.01)
    15–202673.79 (1.94)
Gender<0.0001
    Male6143.50 (2.14)
    Female6353.01 (1.76)
Ethnicity<0.0001
    Chinese8893.05 (1.89)
    Malay2583.94 (1.90)
    Indian and others1023.21 (2.41)
Father’s educational level<0.0001
    1493.79 (1.98)
    23343.56 (1.84)
    35203.28 (2.09)
    41902.81 (1.96)
    51542.84 (1.67)
Reading in books per week0.84
    <2 weeks5543.26 (2.04)
    ⩾2 weeks6883.24 (1.91)
IQ0.0003
    First quartile3283.58 (2.09)
    Second quartile2933.19 (1.85)
    Third quartile2703.08 (1.82)
    Forth quartile2253.01 (1.98)
Parental myopia
    None5403.42 (2.0)0.003
    Either4763.20 (1.92)
    Both2312.98 (1.95)
Height (cm)<0.0001
    <Median 159 cm5762.89 (1.84)
    ⩾Median 159 cm6733.56 (2.02)
  • N, total sample size; SD, standard deviation; 1, no formal education; 2, primary education; 3, secondary education; 4, preuniversity/diploma; 5, university education.