Comparison of Reading Development Across Socioeconomic Status in the United States

It is well known that higher parental socioeconomic status (SES) predicts better child reading outcomes, but little work has been done to unpack this finding. The main overall question addressed by this project was whether cognitive models of the two main reading outcomes, single word reading (SWR) and reading comprehension (RC), performed similarly across levels of parental SES. The current study predicted a differential relation between parental SES and both predictors and outcomes because of the known large relation between parental SES and child oral language development. Three questions examined the mediating effects of cognitive predictors on the relation between parental SES and reading outcomes, the moderating effects of SES on the developmental trajectories of reading outcomes, and the strength of the relationship between SES and the two reading outcomes. Participants were part of two large and comprehensive datasets: the cross-sectional Colorado Learning Disability Research Center (CLDRC; n=1554) sample, and the International Longitudinal Twin Study (ILTS; n=463 twin pairs) sample. In terms of cognitive predictors, the relation between SES and SWR was disproportionately mediated by two language skills, vocabulary (VOC) and phonological awareness (PA). For the RC models, both SWR and oral listening comprehension (OLC) did not disproportionally mediate the relation between RC and SES; however, full mediation was not exhibited. With regard to the trajectory of reading outcomes, SES moderated the starting values of SWR and RC, and the slopes of SWR development. When performance on the control measures of early reading skills (e.g., print knowledge, vocabulary, and decoding skills) was included the models, the moderating effects of SES were completely accounted for by these measures. In terms of outcomes, SES had a stronger relation to RC than to SWR, especially at later ages. These findings have implications for interventions aimed at improving reading outcomes in children from lower SES families.