Research

Organized by category, this page is dedicated to making it easy for you to find research backing up the claims on our home page. Want to know more about developmental milestones for speech and language? Need to see how hearing and vision impact speech development? Wish to know more about how reading to infants and toddlers promotes both early literacy skills and language learning?


Scroll down and find the category you want to know more about! Each link comes from a reputable source.

Language and Speech Developmental Milestones

These may show some differences across resources, as research is constantly being done. In 2018 there were some changes in the age of "mastery" of speech sounds that resulted in recommendations for earlier intervention. The image shown below reflects the 2018 data and years of expected mastery. What we do know is that if there is a delay in speech, earlier intervention generally yields better results. If you are struggling to understand your 3 year old child's speech, it's worth requesting an evaluation through your school system or your pediatrician.

Please note the above image was not created by Cass Kim, but rather is a resource from Tracy W. Marian, M.A. CCC-SLP

How Hearing Impacts Speech and Language Development

How Vision Impacts Speech And Language Development (AKA Why Seeing Lips During Speech Matters)

How Reading to Infants, Toddlers, and Children Impacts Literacy and Language Learning