Meaningful Differences identifies the word gap

By Bryce Edwards• May 3, 2018

In the landmark study published in their book Meaningful Differences in the Everyday Experience of Young American Children, Betty Hart & Todd Risley recorded parent-child spoken interactions in 42 families. They discovered that some children heard 30 million fewer words by their fourth birthdays than others—and that this “word gap” has long-term effects on later child outcomes. Meaningful Differences has had a huge impact in the twenty years since Brookes published it, prompting followup studies on the word gap and major projects like the Thirty Million Words® Initiative.