Table 2

Definitions of amblyopia and amblyopia risk factors

DisorderDefinition
Amblyopia
 1.Unilateral≥2 line difference in best corrected acuity and worse than 20/40 in any eye.
 2.BilateralWorse than 20/40 in the better-seeing eye.
Amblyopia risk factors
 1.StrabismusTropias >10D
 2.Reduced stereoacuity>100 arcsec
 3.Refractive errorsAs defined below
  a.Hyperopia>3.5D
  b.Myopia<−1.5D
  c.Astigmatism>1.5D
  d.Anisometropia>1.5D
  • D, dioptre.