The Relationship Between Morphological Knowledge and Decoding Ability for Swedish Children with Typical Reading Development and Children with Reading Difficulties

Purpose This study investigated the contribution of morphological knowledge (MK) to decoding of multimorphemic words in Swedish children at an early stage of reading development.Method Participants were 299 children in Grade 2 (ages 8–9), including 185 with typical reading development (TRD) and 114 with reading difficulties (RD) (girls n = 156). Children were recruited from 12 schools varying in socioeconomic status and included both first-language (L1) and second-language (L2) learners of Swedish. Mixed-effects linear regression models with random intercepts for school examined the contribution of MK while controlling for working memory, rapid automatized naming, nonword repetition, and general word reading skills.Results For the full sample and TRD group, MK uniquely and significantly predicted decoding of multimorphemic words. Specifically, the ability to manipulate the morphological structure of words was a significant predictor. For children with RD, MK was not a significant predictor, whereas working memory significantly predicted decoding in addition to word reading skills.Conclusion These findings suggest that MK plays a significant role in decoding in Swedish – a semi-transparent orthography with rich morphology – particularly after children have mastered basic grapheme–phoneme correspondences.