Stability of reading and spelling difficulties

Abstract Reading and spelling can be impaired selectively and combined. Research with German-speaking children demonstrated that reading problems are stable over time, while many children with spelling difficulties improve their skills (Moll et al., 2020). Our study aims to examine the stability of literacy impairments in Hungarian elementary school children and explore the cognitive factors that might play a role in remediating literacy deficits. We assessed pupils' reading fluency and spelling skills from grades 2 to 6, categorizing 189 children into four literacy groups. These are combined reading and spelling deficit (RSD), isolated reading deficit (IRD), isolated spelling deficit (ISD), and typically developing (TD) groups. Good performance means less than 0.5 SD deviation from average age-appropriate skills, and poor performance means skills more than 0.9 SD below average. After one to three semesters, we reassessed their literacy skills along with phonological awareness and rapid automatized naming (RAN). The RSD group showed the highest stability, followed by the TD group. Stability was significantly lower in the isolated deficit groups. ISD children who remediated their spelling at t2 performed better on the phonological awareness task than their peers whose spelling remained impaired. Many members of the initial IRD group have changed groups over time but there is no similar pattern as in the ISD group. Our results are in concert with the double deficit hypothesis of dyslexia (Wolf & Bowers, 1999); thus, the most persistent literacy deficit evolves when both reading and spelling are impaired.