title: Development of a Reading Accessibility Index Using the MNREAD Acuity Chart.
abstract: OBJECTIVE
  We define a Reading Accessibility Index for evaluating reading in individuals with normal and low vision.
  
  
  OBJECTIVE
  To compare the Reading Accessibility Index with data from the Impact of Cataracts on Mobility (ICOM) study.
  
  
  METHODS
  This investigation was a secondary data analysis from the ICOM study performed between July 1, 2014, and September 20, 2015, at 12 eye clinics in Alabama from October 1, 1994, through March 31, 1996. Participants were 321 adults with cataract (n = 92), pseudophakia (n = 131), or natural crystalline lenses without cataract (n = 98).
  
  
  METHODS
  The Reading Accessibility Index (hereafter referred to using the abbreviation ACC for the first 3 letters of Accessibility) is defined as an individual's mean reading speed measured across the 10 largest print sizes on the MNREAD Acuity Chart (Precision Vision) (0.4-1.3 logarithm of the minimum angle of resolution at 40 cm), normalized by 200 words per minute, which was the mean value for a group of 365 normally sighted young adults. The ACC is a single-value measure that captures an individual's range of accessible print sizes and reading fluency within this range.
  
  
  RESULTS
  The study cohort comprised 321 participants. Their age range was 55 to 85 years, and 157 (48.9%) were female. The ACCs for the ICOM study participants ranged from 0.19 to 1.33, where 1.00 is the mean value for normally sighted young adults. The ACC for the cataract group (mean [SD], 0.65 [0.18]) was significantly lower than that for the pseudophakia group (mean [SD], 0.77 [0.16]) and the control group (mean [SD], 0.76 [0.19]) (P < .001 for both). The correlation between the ACC and Early Treatment Diabetic Retinopathy Study visual acuity (r = -0.22) and Pelli-Robson contrast sensitivity (r = 0.20) was weaker than that with a reading-related measure of instrumental activities of daily living (r = -0.60) (P < .001 for both).
  
  
  CONCLUSIONS
  The ACC represents an individual's access to text across the range of print sizes found in everyday life. Its calculation does not rely on curve fitting and provides a direct comparison with the performance of normally sighted individuals. Changes in an individual's ACC might be used to evaluate the effect of ophthalmic treatment, rehabilitation programs, or assistive technology on reading accessibility. Data from the ICOM study show that the ACC reflects characteristics of reading performance in everyday life and is sensitive to improved reading accessibility for pseudophakic eyes.
authors: Department of Psychology, University of Minnesota, Minneapolis.
authors: Aurélie
authors: A
authors: Calabrèse
authors: Department of Ophthalmology, The University of Alabama at Birmingham.
authors: Cynthia
authors: C
authors: Owsley
authors: Department of Ophthalmology, The University of Alabama at Birmingham3Department of Epidemiology, The University of Alabama at Birmingham.
authors: Gerald
authors: G
authors: McGwin
authors: Department of Psychology, University of Minnesota, Minneapolis.
authors: Gordon E
authors: GE
authors: Legge
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000407:Alabama; D000554:Ambulatory Care Facilities; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010364:Pattern Recognition, Visual; D011932:Reading; D012016:Reference Values; D013647:Task Performance and Analysis; D013997:Time Factors; D014787:Vision Tests / Q000295:instrumentation*; D015354:Vision, Low / Q000150:complications / Q000175:diagnosis*; D014792:Visual Acuity / Q000502:physiology*; D055815:Young Adult