The repeatability of MNREAD acuity charts and variability at different test distances

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• Accurate measurement of reading performance is crucial for clinical assessment.
• The MNREAD acuity charts are widely used for evaluating reading characteristics.
• Understanding the repeatability and effects of working distance is essential for reliable clinical application.

Purpose of the Study:

• To establish the repeatability of the MNREAD acuity charts.
• To determine the coefficient of repeatability for reading acuity, reading speed, and critical print size.
• To investigate the impact of varying working distances on these reading parameters.

Main Methods:

• Thirty healthy young adults participated in the study.
• Test-retest repeatability was assessed using MNREAD charts at a 40 cm working distance over two sessions.
• Measurements were repeated at 24 cm and 52 cm, with chart version and distance randomized.

Main Results:

• The coefficient of repeatability was +/- 0.05 logMAR for reading acuity and +/- 0.12 logMAR for critical print size.
• Reading speed showed a repeatability coefficient of +/- 8.6 words per minute.
• Reading acuity and critical print size were significantly affected by testing distance (p=0.001), while reading speed was not (p=0.27).

Conclusions:

• The MNREAD acuity charts demonstrate reliable repeatability for assessing reading acuity, speed, and critical print size.
• The findings support the use of MNREAD charts in normal adult populations.
• Clinicians should be aware of the influence of working distance on reading acuity and critical print size measurements.