Score for log of minimum angle of resolution (MAR), as part of the NIH Toolbox Sensation Domain Vision Measure Visual Acuity Test

The NIH Toolbox Visual Acuity Test directly measures participants visual acuity, or distance vision. The participant is seated 12.5 feet away from a computer monitor at eye level, and letters (called optotypes) are displayed one at a time on the screen for the participant to identify, using both eyes at the same time, with the participant wearing his/her normal corrective lenses for distance vision (glasses or contact lenses, if worn). As the participant successfully identifies optotypes of a given size, smaller ones appear on the screen, until the computer program ascertains the smallest-size optotype the participant can successfully see. Conversely, the program displays larger optotypes if the participant cannot see the letter size that is first displayed, until a size that he/she can accurately see is found. For participants ages 3 to 7 only the letters H, O, T, and V are used, and children may point to a laminated card showing the letters if they cannot verbalize or cannot recall the letter names. For participants ages 8 and above, the entire set of optotypes is used, following a common protocol used in professional vision testing. This test takes approximately three minutes to administer and is recommended for ages 3-85.

2016-06-03

Copyright 2006-2012 National Institutes of Health and Northwestern University. http://www.nihtoolbox.org/WhatAndWhy/Sensation/Vision/Pages/NIH-Toolbox-Visual-Acuity-Test-.aspx

LogMAR Score (range from -0.3 (best possible score) to 1.7 (worst possible score))