Early productive vocabulary predicts academic achievement 10 years later

Abstract

We use a longitudinal design to examine associations for a diverse sample of 2,120 Danish 16- to 30-month-old children between early expressive vocabulary and later reading and math outcomes in the sixth grade. Educational outcomes, in particular decoding and reading comprehension, can be predicted from an early vocabulary measure as early as 16 months with effect sizes (in proportion of variance accounted for) comparable to 1 year's mean growth in reading scores. The findings confirm in a relatively large population-based study that late talkers are at risk for low educational attainment because the majority of children experiencing early language delay obtain scores below average in measures of reading in the sixth grade. Low scores have the greatest predictive power, indicating that children with early delays have elevated risk for later reading problems.

What matters most when it comes to vocabulary and language development?

“…Vocabulary development is important because educational outcomes can be predicted from measures of language development when children are less than two years of age. Delay in a child's productive vocabulary reported by its parents at this age can later be comparable to one year's mean growth in reading scores .…”

Multilingual Toddlers’ Vocabulary Development in Two Languages: Comparing Bilinguals and Trilinguals

“…Vocabulary at this age is readily measured via parent-report questionnaires, which have a high degree of reliability and validity (Dale, 1991;Fenson et al, 2007). Understanding early vocabulary development is important, as vocabulary size has been shown to predict later academic achievement (Bleses, Makransky, Dale, Højen, & Ari, 2016;Marchman & Fernald, 2008). Vocabulary size is highly variable across children, whether they are from monolingual or multilingual backgrounds (De Houwer, Bornstein, & Putnick, 2014;Frank, Braginsky, Marchman, & Yurovsky, in press).…”

School‐age outcomes of late‐talking toddlers: Long‐term effects of an early lexical deficit

“…Other studies that report school‐age outcomes including reading and spelling assessments found relationships between early language assessments (as expressive vocabulary size) and reading outcomes prior to school enrolment (Hammer et al, , large‐scale), at early adolescence in TDC (Bartl‐Pokorny et al, ) and in population‐based studies (Bleses, Makransky, Dale, Hojen, & Ari, ; Lee, ).…”