A normative study of the accommodative lag in elementary school children.

Limited normative information is available regarding the accommodative lag of elementary school children. The accommodative lag of approximately 100 children in each of the grades kindergarten to grade six was measured using the Monocular Estimate Method (MEM) of dynamic retinoscopy. Children were selected on the basis of passing school screening using Modified Clinical Technique (MCT) criteria. Habitual spectacle corrections were worn and MEM retinoscopy was performed at the child's usual working distance. The mean lag for the total population of children was OD +0.33 D (+/- 0.35), OS +0.35 D (+/- 0.34). Scatter plots show a weak relation between MEM and the other variables; however, the one-way analysis of variance of MEM against age and grade show that a dependency exists.