Literacy as a Unidimensional Multilevel Construct: Validation, Sources of Influence, and Implications in a Longitudinal Study in Grades 1 to 4

This study examined the extent to which literacy is a unitary construct, the differences between literacy and general language competence, and the relative roles of teachers and students in predicting literacy outcomes. Much of past research failed to make a distinction between variability in outcomes for individual students and variability for outcomes in the classrooms students share (i.e., the classroom level). Utilizing data from 1,342 students in 127 classrooms in Grades 1 to 4 in 17 high-poverty schools, confirmatory factor models were fit with single- and two-factor structures at both student and classroom levels. Results support a unitary literacy factor for reading and spelling, with the role of phonological awareness as an indicator of literacy declining across the grades. Writing was the least related to the literacy factor but the most impacted by teacher effects. Language competence was distinct at the student level but perfectly correlated with literacy at the classroom level. Implications f...