Structural validity of an instrument for the evaluation of Irlen syndrome

Visual Perception Distortions and Physical Discomfort, Irlen Syndrome (IS) signs and symptoms hinder the reading process. One of the principal forms of IS screening and the most commonly used in investigations worldwide has been the Irlen Perceptual Reading Scale (IRPS) 1988 and the Ecuadorian version scale.
However, the results obtained when applying these scales usually present limitations in the diagnosis. This study aimed to update the IRPS validity through confirmatory factor analysis in its Ecuadorian version (Vilchez, Bernal 2018). Participants were 252 fourth and fifth-graders from 14 schools in Cuenca, Ecuador.
The authors assessed a factor model using a DWLS estimator with a polychoric correlations matrix. The five correlated first-order factors presented adequate fit goodness. Irlen Screeners can use the new validated IRPS version as a screening instrument for Irlen diagnosis.