Developmental Monitoring and Screening

Developmental Monitoring

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Developmental monitoring observes how your child grows and changes over time and whether your child meets the typical developmental milestones in playing, learning, speaking, behaving, and moving. Parents, grandparents, early childhood providers, and other caregivers can participate in developmental monitoring. You can use a brief checklist of milestones to see how your child is developing. If you notice that your child is not meeting milestones, talk with your doctor or nurse about your concerns.

When you take your child to a well visit, your doctor or nurse will also do developmental monitoring. The doctor or nurse might ask you questions about your child’s development or will talk and play with your child to see if he or she is developing and meeting milestones. A missed milestone could be a sign of a problem, so the doctor or another specialist will take a closer look by using a more thorough test or exam.

Your childcare provider can also be a valuable source of information on how your child develops. More information on developmental monitoring for early childhood educators.

Developmental Screening

Developmental screening takes a closer look at how your child is developing. Your child will get a brief test, or you will complete a questionnaire about your child. The tools used for developmental and behavioral screening are formal questionnaires or checklists based on research that ask questions about a child’s development, including language, movement, thinking, behavior, and emotions. Developmental screening can be done by a doctor or nurse, but also by other professionals in healthcare, early childhood education, community, or school settings.

Developmental screening is more formal than developmental monitoring and normally done less often than developmental monitoring. Your child should be screened if you or your doctor have a concern. However, developmental screening is a regular part of some of the well-child visits for all children even if there is not a known concern.

The American Academy of Pediatrics (AAP) recommends developmental and behavioral screening for all children during regular well-child visits at these ages:1

  • 9 months
  • 18 months
  • 30 months

In addition, AAP recommends that all children be screened specifically for autism spectrum disorder (ASD) during regular well-child visits at:

  •  18 months
  •  24 months

If your child is at higher risk for developmental concerns due to preterm birth, low birthweight, environmental risks like lead exposure, or other factors, your healthcare provider may also discuss additional screening. If a child has an existing long-lasting health concern or a diagnosed condition, the child should have developmental monitoring and screening in all areas of development, just like those without special healthcare needs.

If your child’s healthcare provider does not periodically check your child with a developmental screening test, you can ask that it be done.

Fact Sheet on Developmental Monitoring and Screening

Developmental Evaluation

A brief test using a screening tool does not provide a diagnosis, but it indicates if a child is on the right development track or if a specialist should take a closer look. If the screening tool identifies an area of concern, a formal developmental evaluation may be needed. This formal evaluation is a more in-depth look at a child’s development, usually done by a trained specialist, such as a developmental pediatrician, child psychologist, speech-language pathologist, occupational therapist, physical therapist, or other specialist. The specialist may observe the child, give the child a structured test, ask the parents or caregivers questions, or ask them to fill out questionnaires. The results of this formal evaluation determines whether a child needs special treatments or early intervention services or both.

Developmental Monitoring

WHO:     You — parents, grandparents, other caregivers

WHAT:   Look for developmental milestones

WHEN:   From birth to 5 years

WHY:      To help you

  • celebrate your child’s development
  • talk about your child’s progress with doctors and childcare providers
  • learn what to expect next
  • identify any concerns early

HOW:     With easy, free checklists – get yours at

Developmental Screening

WHO:     Healthcare provider, early childhood teacher, or other trained provider

WHAT:   Look for developmental milestones


  • Developmental Screening at 9, 18, 30 months of age
  • Autism Screening at 18 and 24 months of age

WHY:      To find out

  • if your child needs more help with development, because it is not always obvious to doctors, childcare providers, or parents
  • if more developmental evaluation are recommended

HOW:     With a formal, validated screening tool – learn more

Developmental Evaluation

WHO:     Developmental pediatrician, child psychologist, or other trained provider

WHAT:   Identify and diagnose developmental delays and conditions

WHEN:   Whenever there is a concern

WHY:      To find out

  • if your child needs specific treatment
  • if your child qualifies for early intervention

HOW:     With a detailed examination, formal assessment tools, observation, and surveys from parents and other caregivers, often in combination, depending on the area of concern

Why It’s Important

Many children with developmental delays or behavior concerns are not identified as early as possible. As a result, these children must wait to get the help they need to do well in social and educational settings (for example, in school, at home, and in the community).

In the United States, about 1 in 6 children aged 3 to 17 years have one or more developmental or behavioral disabilities, such as autism, a learning disorder, or attention-deficit/hyperactivity disorder2. In addition, many children have delays in language or other areas that can affect how well they do in school. However, many children with developmental disabilities are not identified until they are in school, by which time significant delays might have occurred and opportunities for treatment might have been missed.

Services for Children with Developmental Disabilities

Research shows that early intervention treatment services can improve a child’s development.

  • Early intervention services can help children from birth through 3 years of age (36 months) learn important skills.
  • For children age 3 and older with an identified developmental delay or disability, special education services may be provided.

Services can include a variety of options, depending on the child’s need, such as therapy to help the child talk, move and walk, learn, and interact with others.

Child Find programs are provided by each state to evaluate and identify children who need special education services.  Early intervention programs can provide services from birth to 3 years of age. Local public school systems can provide the needed services and support for children age 3 years and older. Children can access some services even if they do not attend public school.

The Individuals with Disabilities Education Act (IDEA) says that children with a diagnosed disability should get special education services. IDEA says that children younger than 3 years of age who are at risk of having developmental delays might be eligible for early intervention treatment services even if the child has not received a formal diagnosis. Treatment for particular symptoms, such as speech therapy for language delays, may not require a formal diagnosis.

Although early intervention is extremely important, intervention at any age can be helpful. It is best to get an evaluation early so that any needed interventions can get started. When parents are concerned about a child’s development, it can be very challenging for them to figure out the right steps to take. States have created parent centers. These centers help families learn how and where to have their children evaluated and how to find services. For information about services in your state, you can access your state’s parent center.

Links to Other Websites

“Learn the Signs. Act Early.”
This CDC program offers free milestone checklists to help parents and professionals track children’s milestones, support development, share concerns, and take action to support developmental delays.

Birth to 5: Watch Me Thrive!
Birth to 5: Watch Me Thrive! is a coordinated federal effort to encourage healthy child development, universal developmental and behavioral screening for children, and support for the families and providers who care for them.

Overview of Early Intervention
Learn more about early intervention services from the Center for Parent Information and Resources.

Bright Futures
Bright Futures materials for families are available on a wide range of mental, physical, and emotional health issues in children from before birth through 21 years of age.


  1. Lipkin PH, Macias MM, Council on Children with Disabilities, Section on Developmental and Behavioral Pediatrics (2020). Promoting optimal development: Identifying infants and young children with developmental disorders through developmental surveillance and screening. Pediatrics, 145(1), e20193449.
  2. Zablotsky B, Black LI, Maenner MJ, Schieve LA, Danielson ML, Bitsko RH, Blumberg SJ, Kogan MD, Boyle CA. Prevalence and Trends of Developmental Disabilities among Children in the US: 2009–2017. Pediatrics. 2019; 144(4):e20190811. [Read summary]