SLP Expert Opinion: Milestones vs Averages and Why Developmental Milestones Have Changed

young child with a walker showing new milestones

You’re frustrated. Other kids the same age as your child are talking so much more than yours is, but your pediatrician is saying there is nothing to worry about. People are saying the developmental milestones changed recently too. What does all this mean, and what should you do next?

Let’s dive right in and answer these questions!

The Pediatrician Says Don’t Worry

There’s a lot of talk about milestones when you have little ones, but one of the most frequently asked questions I hear is “Why don’t the milestones SLPs talk about match what my child’s pediatrician says?” 

This is largely due to the difference in milestones vs averages.

Milestones vs Averages

Milestones are the level that 90% of children that age have achieved for a particular skill.

Averages are the midpoint. That is where 50% of children are. So, up until now, the pediatric development guidelines were based on the AVERAGE, even though they were worded as “milestones”. Confusing, right?!

SLPs and pediatricians have looked at this data differently.

A pediatrician has been viewing the standard for referrals at the 50th percentile range while SLPs often consider children delayed if they are below the true milestone (90th percentile).

While pediatricians are responsible for knowing about a vast range of information for ages birth through 21, SLPs hone in on much more specific skills. 

>>>So, the data my pediatrician has is wrong?

No, but it wasn’t interpreted in the clearest way. Because of this, the American Academy of Pediatrics (AAP) recently updated the information. 

Changes in Developmental Milestones

The AAP updated the childhood developmental milestones in 2022. Before this, these guidelines had not been updated since they were first released in 2004– that’s almost 20 years! 

When created, the guidelines were based on the abilities of the 50th percentile of children. Now, they reflect the skills of children in the 75th percentile.This is good news! This change makes it easier for practitioners to better identify children who are developmentally delayed!

Review this comprehensive milestone checklist created by the CDC that corresponds with your child’s age (from 2 months through 5 years old) to check in on your child’s skill level.  

So, the difference in “milestones” and “averages” and the updated milestones list might leave you realizing that your child is much further behind than you thought. Yikes! 

young boy playing with playdoh demonstrating averages and milestones

What are the Next Steps?

For Parents

There are a few steps you can take next:

Talk to Your Pediatrician Again

Don’t be afraid to advocate for your child if it doesn’t seem like your pediatrician is on board. 

You know your child best and now have better data to support your intuition. Be confident and bring this to your pediatrician’s attention if needed.

Take a Webinar

If your child is not meeting milestones for his age, sign up for one of my highly reviewed webinars!  

Talk to an SLP Near You

You can also consider contacting your local early intervention program or scheduling a speech language evaluation privately. 

For SLPs

Advocate, advocate, advocate… and keep learning!

If you’re an SLP and parent of a young child, use your child’s well visits as a mini-education session. Mention the changes to the guidelines and see if you can clarify any questions your pediatrician might have. 

Check out my Early Language Masterclass! This two-hour webinar will leave you with practical therapy tips for working with language-delayed toddlers and resources to share with parents.

Use these Early Language Parent Handouts to educate caregivers.

Data and its interpretation is always changing, so we just keep learning and growing together. Remember, you’re already equipped to help your child!

You might also be interested in reading:

What to Expect from a Speech and Language Evaluation

Why is Early Intervention Important?

Recognizing the Early Signs of Autism

Expectations for Speech Clarity

Click here for a FREE handout on talking to caregivers. These quick tips will boost your confidence immediately!


This Post Has One Comment

  1. Meghan

    This is great, nice to see how everyone can play a part in helping kids get the services they need!

Comments are closed.


The views expressed in this blog are my own and are intended to inspire other speech-language pathologists in their own practice. If you are a parent, teacher or other educator, these ideas are not intended to take the place of treatment by a certified clinician. Read full disclaimer here.