A controlled field study of the use of coloured overlays on reading achievement

Abstract

This study investigated the effects of using Irlen coloured overlays on reading rate, accuracy, fluency and comprehension under regular class conditions, with class teachers instigating the study and conducting the assessment. All subjects in grade 3 at Whitney and McKinley Elementary schools were screened for symptoms of Irlen syndrome, with 31 subjects identified at Whitney and 40 subjects identified at McKinley. The effects on reading achievement were investigated under conditions of immediate use and delayed use, with one group (Whitney) provided optimum coloured overlays for 3 months and the other group (McKinley) delayed treatment for 3 months. The effects were then assessed for a further three months with both groups.

After three months of use of overlays, the Whitney group demonstrated a significant improvement in reading achievement with mean gains in grade equivalence scores of between 1 year 2 months and 1 year 7 months. However, between the three to six month period of use, the gains for the Whitney group reached a plateau, with no significant improvement in reading achievement. The McKinley group had negligible gains in reading achievement during the first 3 months without the use of overlays, but significant gains during the 3 month to 6 month phase with the use of overlays, which ranged from 1 year 8 months to 2 years 8 months. It was suggested that the reported reduction in print and background distortions may improve accuracy of word recognition and allow attention to be directed more to the meaning of what is being read than to word recognition thus enhancing reading comprehension. The plateau effect identified for the Whitney group between 3 and 6 months could be related to the fact that after 3 months of overlay use, many students had reached grade level in reading achievement.