# Arabic Reading Performance With a Chromatic Acuity Chart

## TL;DR

This study compares how well people read Arabic text using different color contrasts, finding that achromatic charts perform better for reading accuracy.

## Contribution

The study establishes a baseline for chromatic contrast effects on Arabic reading and identifies differences in performance between chromatic and achromatic charts.

## Key findings

- Red-on-green charts had slightly higher maximum reading speed but lower reading acuity compared to achromatic charts.
- Individuals with red–green color vision deficiencies performed worse on red-on-green charts.
- Lower background luminance and contrast in chromatic charts led to reduced reading acuity and larger critical print size.

## Abstract

This study compared the reading performance for Arabic text defined by chromatic and achromatic contrast to understand better how chromatic contrast affects reading of normally sighted individuals and to establish a baseline for determining whether patients have a selective red–green chromatic sensitivity loss.

Reading performance for Arabic text was accessed by examining maximum reading speed (MRS), reading acuity (RA), critical print size (CPS), and the Reading Accessibility Index (ACC) using three near-point charts. The charts were the black-on-white Balsam Alabdulkader–Leat (BAL) chart, a red-on-green chart, and a gray-on-gray chart with a background luminance equal to the chromatic chart.

The MRSs were significantly different (P = 0.03), with the red-on-green chart having a slightly higher value than the BAL chart. The ACC was lower for the BAL chart than the red-on-green and gray charts (P = 0.003). However, RA for the BAL chart was better, and the CPS was smaller relative to the red-on-green chart (P < 0.05) and gray chart (P < 0.001). Individuals with red–green color vision deficiencies had poorer RA and larger CPS on the red-on-green chart relative to the achromatic charts.

Although the MRS and ACC of the chromatic chart were significantly higher, the difference was not clinically important. The result that the MRS was similar for all three charts confirmed earlier findings that MRS is similar if text contrast is sufficiently above threshold. The lower RA and corresponding larger CPS for the red-on-green and gray charts were due to their lower background luminance and lower contrast.