title: The repeatability of MNREAD acuity charts and variability at different test distances.
abstract: OBJECTIVE
  The purposes of this study are to establish the repeatability of the MNREAD acuity charts in a normal adult population and to determine the coefficient of repeatability for reading acuity, reading speed, and critical print size. The study also investigates how changing the working distance affects these parameters.
  
  
  METHODS
  Thirty normal young adults (mean age, 23.3 years) participated. Test-retest repeatability was assessed at 40 cm over two sessions by the same examiner using MNREAD charts 1 and 2. Additional measurements were also carried out at 24 cm and 52 cm working distances. The distance and the version of the chart used were randomized.
  
  
  RESULTS
  The coefficient of repeatability was found to be +/- 0.05 logarithm of the minimum angle of resolution (logMAR) for reading acuity, +/- 0.12 logMAR for critical print size, and +/- 8.6 words per minute for reading speed. Reading acuity and critical print size changed significantly with testing distance (p = 0.001). No changes were found in the reading speed at the different test distances (p = 0.27).
  
  
  CONCLUSIONS
  The MNREAD acuity charts can be used reliably to measure reading acuity, reading speed, and critical print size in a normal adult population.
authors.affiliation: Department of Optometry and Visual Science, City University, London, UK. Ahalya.Subramanian.1@city.ac.uk
authors.forename: Ahalya
authors.initials: A
authors.lastname: Subramanian
authors.forename: Shahina
authors.initials: S
authors.lastname: Pardhan
mesh_terms: D000293:Adolescent; D000328:Adult; D006801:Humans; D010364:Pattern Recognition, Visual / Q000502:physiology; D011932:Reading; D012016:Reference Values; D015203:Reproducibility of Results; D014787:Vision Tests / Q000295:instrumentation*; D014792:Visual Acuity / Q000502:physiology*