Changes in refraction between the ages of 1 and 3 1/2 years.

A study has been made of the changes in refraction as a sample of 148 children grew between the ages of 1 and 3 1/2 years. There was no decrease in hypermetropia, but there was a significant decrease in the incidence of astigmatism. Study of the changes in the refraction in the horizontal and vertical meridia of individual eyes gave clear evidence of a trend towards emmetropia if the initial refraction in either meridian was myopic or less than +2.50 D. Above that level the refraction became more or less hypermetropic.