John T Tassinari1. 1. Southern California College of Optometry, Fullerton, California, USA. jtod@sbcglobal.net
Abstract
BACKGROUND: Monocular estimate (estimation) method (MEM) is a widely used clinical test of accommodative response. Normative data for MEM are available based on the central tendency measures from a population of schoolchildren but not a clinical population. Also, the relationship of accommodative response to refractive status and heterophoria has been researched, but not with MEM as the determinant of the manifestation of accommodative response. METHODS: A group of 211 pre-presbyopic clinical subjects were tested with MEM for purposes of comparing the central tendency measures of a clinical population to established normative data and determining whether MEM varied with refractive status or near phoria. RESULTS: A lag of about one-third diopter was the mean MEM result for this clinical population. The median was +0.25 D. Myopia and near esophoria have a statistically significant relationship to MEM. CONCLUSIONS: The central tendency measures derived from MEM administered to this population replicate the central tendency measures found in a previous normative study. This study provides preliminary evidence that the difference between accommodative response and accommodative stimulus, as measured by MEM, may be influenced by myopia and esophoria.
BACKGROUND: Monocular estimate (estimation) method (MEM) is a widely used clinical test of accommodative response. Normative data for MEM are available based on the central tendency measures from a population of schoolchildren but not a clinical population. Also, the relationship of accommodative response to refractive status and heterophoria has been researched, but not with MEM as the determinant of the manifestation of accommodative response. METHODS: A group of 211 pre-presbyopic clinical subjects were tested with MEM for purposes of comparing the central tendency measures of a clinical population to established normative data and determining whether MEM varied with refractive status or near phoria. RESULTS: A lag of about one-third diopter was the mean MEM result for this clinical population. The median was +0.25 D. Myopia and near esophoria have a statistically significant relationship to MEM. CONCLUSIONS: The central tendency measures derived from MEM administered to this population replicate the central tendency measures found in a previous normative study. This study provides preliminary evidence that the difference between accommodative response and accommodative stimulus, as measured by MEM, may be influenced by myopia and esophoria.