Table 4 Risk-factor analysis for strabismus, amblyopia and hypermetropia: odds ratios (OR) before and after mutual adjustment in 7538 children
Risk factorUnadjusted OR (95% CI)Final model (A) OR adjusted for risk factors* (95% CI)Final model (B) OR further adjusted for the other eye problems (95% CI)
p Valuep Valuep Value
Clinically significant convergent strabismus
First-degree relative with squint/amblyopiap<0.001p<0.001p = 0.099
    Yes2.53 (1.89 to 3.39)2.39 (1.72 to 3.20)1.38 (0.94 to 2.03)
    No1.0 referent1.0 referent1.0 referent
Parental hypermetropiap = 0.002p = 0.017p = 0.382
    Yes1.86 (1.25 to 2.77)1.62 (1.09 to 2.44)1.24 (0.76 to 2.02)
    No1.0 referent1.0 referent1.0 referent
Prematurityp = 0.001p<0.001p = 0.001
    Yes2.67 (1.78 to 4.00)2.54 (1.65 to 3.93)2.47 (1.44 to 4.23)
    No1.0 referent1.0 referent1.00 referent
Clinically significant divergent strabismus
Sexp = 0.089p = 0.050p = 0.055
    Male1.0 referent1.0 referent1.0 referent
    Female1.67 (0.93 to 3.01)1.86 (1.00 to 3.44)1.84 (0.99 to 3.41)
Mother smoked in last two weeks pregnancyp = 0.002p = 0.004p = 0.007
    Yes2.78 (1.47 to 5.26)2.55 (1.34 to 4.87)2.46 (1.27 to 4.73)
    No1.0 referent1.0 referent1.0 referent
Intrauterine growth retardationp<0.001p = 0.001p = 0.002
    Yes6.40 (2.96 to 13.84)4.49 (1.86 to 10.86)4.31 (1.74 to 10.69)
    No1.0 referent1.0 referent1.0 referent
Amblyopia
First-degree relative with squint/amblyopiap = 0.001p<0.001p<0.001
    Yes2.77 (2.13 to 3.59)2.72 (2.04 to 3.63)2.05 (1.43 to 2.94)
    No1.0 referent1.0 referent1.0 referent
Parental hypermetropiap<0.001p = 0.006p = 0.641
    Yes2.05 (1.45 to 2.90)1.69 (1.16 to 2.47)1.11 (0.68 to 1.79)
    No1.0 referent1.0 referent1.0 referent
Housing at 8 monthsp = 0.001p = 0.048p = 0.426
    Owned/mortgaged1.0 referent1.0 referent1.0 referent
    Council rented1.85 (1.28 to 2.60)1.51 (1.01 to 2.25)1.03 (0.62 to 1.70)
    Other0.64 (0.33 to 1.26)0.66 (0.33 to 1.30)0.59 (0.26 to 1.32)
Mother smoked in first trimesterp = 0.023p = 0.058p = 0.016
    Yes1.40 (1.04 to 1.86)1.38 (0.99 to 1.92)1.64 (1.10 to 2.45)
    No1.0 referent1.0 referent1.0 referent
Hypermetropia
Child’s ethnicityp = 0.016p = 0.016p = 0.028
    White1.0 referent1.0 referent1.0 referent
    Non-white0.34 (0.14 to 0.82)0.19 (0.04 to 0.72)0.16 (0.03 to 0.82)
First-degree relative with squint/amblyopiap<0.001p<0.001p = 0.011
    Yes2.34 (1.85 to 2.94)2.21 (1.69 to 2.88)1.54 (1.11 to 2.16)
    No1.0 referent1.0 referent1.0 referent
Parental hypermetropiap<0.001p<0.001p = 0.001
    Yes2.08 (1.54 to 2.80)1.94 (1.40 to 2.69)1.90 (1.29 to 2.81)
    No1.0 referent1.0 referent1.0 referent
Parental social classp = 0.034p = 0.048Linear p = 0.027
    I1.0 referent1.0 referent1.0 referent
    II1.44 (0.99 to 2.10)1.49 (0.99 to 2.23)1.47 (0.91 to 2.37)
    III (NM)1.76 (1.19 to 2.61)1.83 (1.20 to 2.82)1.78 (1.07 to 2.95)
    III (M)/IV/V1.67 (1.08 to 2.58)1.50 (0.91 to 2.46)1.82 (1.03 to 3.23)
Housing at 8 monthsp<0.001p<0.001p = 0.013
    Owned/mortgaged1.0 referent1.0 referent1.0 referent
    Council rented1.89 (1.39 to 2.56)2.03 (1.41 to 2.93)1.81 (1.16 to 2.82)
    Other0.90 (0.55 to 1.49)0.72 (0.39 to 1.34)0.65 (0.31 to 1.39)
Prematurityp = 0.001p = 0.034p = 0.607
    Yes2.31 (1.57 to 3.38)1.72 (1.04 to 2.83)1.20 (0.60 to 2.38)
    No1.0 referent1.0 referent1.0 referent

  • *All adjusted analyses included sex, family history of strabismus/amblyopia, parental hypermetropia, child ethnicity, parental SC, type of housing at 8 months, prematurity, IUGR, maternal smoking in first trimester, maternal smoking in late pregnancy. Only variables where p<0.1 were retained in the final model (A). The other vision problems were then added for model (B).