Differential Contributions of Morphological Awareness and Vocabulary to Reading Comprehension in Arabic-Speaking Children With and Without Dyslexia

This study examined the predictive role of morphological awareness and vocabulary in reading comprehension among Arabic-speaking fourth-grade students with and without dyslexia. A total of 296 students from public schools in Oman participated, including two matched subgroups of 37 students each. Morphological awareness was assessed through decomposition and production tasks, alongside vocabulary and reading comprehension measures. Independent samples t-tests revealed that children with dyslexia scored significantly lower than their peers in vocabulary, morphological awareness, and reading comprehension, with large effect sizes. Multiple regression indicated that vocabulary, generating morphemes, and segmenting morphemes together accounted for 47% of the variance in comprehension, with vocabulary emerging as the strongest predictor. Quantile regression revealed differential effects: vocabulary and generating morphemes were more influential at lower comprehension levels, while segmenting morphemes dominated at higher levels. These findings highlight the importance of both lexical knowledge and morphological processing in Arabic reading comprehension and demonstrate that their relative contributions vary across proficiency levels. The results underscore the need for targeted, skill-specific interventions, particularly for children with dyslexia, and support the inclusion of morphological awareness measures in literacy assessments for morphologically rich languages.