Research has shown that language plays an important role in ensuring child's success in later years.
The more skills children bring with them to kindergarten - in basic math, reading, even friendship, and cooperation - the more likely they will succeed in those same areas in school.
Now, according to a University of Washington-led study, it's time to add language to that mix of skills, said a new University of Washington-led study.
Not only does a child's use of vocabulary and grammar predict future proficiency with the spoken and written word, but it also affects performance in other subject areas.
Language, in other words, supports academic and social success, said researcher Amy Pace.
"A lot of other research focuses on math, science, and literacy, and they don't even consider that language could be playing a role," she said. "But really, it emerges as a strong predictor across subject areas. Why do kids succeed in math, for example? Part of it could be having a strong math vocabulary."
The study was the first to look at a comprehensive set of school readiness skills and to try to determine what is the most solid predictor of a child's later success.
Language - the ability to fluidly learn words and to string them together into sentences - was the hands-down winner, said co-author Kathy Hirsh-Pasek.
For this study Pace and her colleagues examined longitudinal data from more than 1,200 children. That study used several measures of academic and social skills at specific ages and grade levels, including evaluations upon entry to kindergarten and in grades 1, 3 and 5.
The team analysed academic and behavioral assessments, assigned standardized scores and looked at how scores correlated in grades 1, 3, and 5. Growth curve modeling allowed the team to look at children's levels of performance across time and investigate rates of change at specific times in elementary school.
Researchers found that of the skills and milestones evaluated - social/emotional, attention, health, reading, math and language - only language skills, when a child entered school, predicted his or her performance both within that subject area and most others (math, reading, and social skills) from first through fifth grade.
Reading ability in kindergarten predicted reading, math and language skills later on; and math proficiency correlated with math and reading performance over time.
People often confuse language with literacy, Pace said. Reading skills include the ability to decode letter and sound combinations to pronounce words, and to comprehend word meanings and contexts.
Language is the ability to deploy those words and use complex syntax and grammar to communicate in speech and writing. And that's why it has such potential to affect other areas of development, Pace said.
The findings from the study are published in the journal Early Childhood Research Quarterly....