The Centers for Disease Control and Prevention and the American Academy of Pediatrics have updated the checklists that outline developmental milestones for infants and young children. This is the first time the checklists have been revised since they were released in 2004.

The purpose of these checklists is to help identify delays earlier and are used as part of annual well visits by pediatricians.

“The Centers for Disease Control and Prevention’s (CDC) Learn the Signs. Act Early. program, funded the American Academy of Pediatrics (AAP) to convene an expert working group to revise its developmental surveillance checklists,” says the AAP. “The goals of the group were to identify evidence-informed milestones to include in CDC checklists, clarify when most children can be expected to reach a milestone (to discourage a wait-and-see approach), and support clinical judgment regarding screening between recommended ages.”

The previous checklists used the 50th percentile to compare child development — meaning that half of children were expected to meet the milestone at a given age. The new checklists use a 75th percentile guideline, which means 75 percent or more children are expected to hit the given target by the outlined age.

From birth to age 5, your child should reach milestones in how he plays, learns, speaks, acts and moves, says the CDC. They advise parents to track their child’s development and act early if they have a concern. It’s all in an effort to encourage healthy child development — and to let parents know that the sooner they intervene when there is a delay, the more effective help can potentially be for their child.

Other changes include added checklists for children at ages 15 and 30 months, additional social and emotional milestones, including when a baby should smile and try to get your attention and open-ended questions to discuss with your pediatrician.

There are also activities outlined that can help promote healthy child development.

And while checklists can be helpful, it’s important to remember that you know your child best — if you have any concerns about their development, don’t delay — talk to your pediatrician today.