What Reading Disability? Evidence for Multiple Latent Profiles of Struggling Readers in a Large Russian Sibpair Sample With at Least One Sibling at Risk for Reading Difficulties.

In this study, we performed a latent profile analysis of reading and related skills in a large ( n = 733) sibpair sample of Russian readers at risk for reading difficulties. The analysis suggested the presence of seven latent profiles, of which two were characterized by relatively high performance on measures of spelling and reading comprehension and the remaining five included severely as well as moderately affected readers with deficits in the domains of phonological, orthographic, and morphological processing. The results suggest that the development and manifestation of reading difficulties in Russian is mappable on a complex pattern of interactions between different types and severities of processing deficits. The results point to the psychological reality of multiple different suboptimal patterns of deficits in reading and reading-related skills and support the multifactorial view of the disorder, with intriguing implications for future neurobiological studies.