The simple view of reading posits that reading comprehension can be decomposed into a print-specific component (concerning decoding and sight word reading) and a language comprehension component (concerning verbal and metalinguistic skills not related to print). One might properly consider lexical skills, indexed by vocabulary measures, part of…

Genetic and environmental relations between vocabulary and reading skills were explored longitudinally from preschool through Grades 2 and 4. At preschool there were strong shared-environment and weak genetic influences on both vocabulary and print knowledge but substantial differences in their source. Separation of etiology for vocabulary and…