Eligibility Criteria
astigmatism, strabismus, ocular abnormalities, anisometropia
SYSTEMIC DISEASE, ASTIGMATISM, STRABISMUS, MYOPIA, -11, ANISOMETROPIA
Eligible participants were primary school students in grades 1 to 4 (aged 6-11 years) with premyopia, defined as a cycloplegic spherical equivalent refraction (SER) of the more myopic eye in the range of −0.50 to 0.50 (inclusive) diopters (D) and having at least 1 parent with an SER in either eye of −3.00 D or less. Children were excluded if they had astigmatism of 1.50 D or more, anisometropia of 1.50 D or more, strabismus and other ocular abnormalities, any systemic diseases, or a history of any myopia interventions.