The looking-while-listening (LWL) paradigm is frequently used to measure toddlers' lexical processing efficiency (LPE). Children's LPE is associated with vocabulary size, yet other linguistic, cognitive, or social skills contributing to LPE are not well understood. It also remains unclear whether LPE measures from two types of LWL trials…

This study employs the Specificity Principle to examine the relative impacts of external (input quantity at home and at school, number of books and reading frequency at home, teachers' degree and experience, language usage, socioeconomic status) and internal factors (children's working memory, nonverbal intelligence, learning-related…