Variation and correlation of clinical tests of accommodative function in a sample of school-age children.

Accommodative facility, lag of accommodation, accommodative response, and relative accommodation were measured in 244 school-age (7.9 to 15.9 years of age) children. The tests studied included monocular estimate method (MEM) dynamic retinoscopy, Nott dynamic retinoscopy, low neutral dynamic retinoscopy, the binocular cross cylinder test, lens accommodative rock (facility), distance (near-far) accommodative rock, negative relative accommodation (NRA), and positive relative accommodation (PRA). The mean, standard deviation, and range of test findings of each test are presented. Coefficients of correlation among the various tests are presented.