Screening Tests and the Diagnostic Process


The process of monitoring children for abnormal conditions is an ongoing challenge for families and primary care clinicians. Part of the difficulty is that “normal” encompasses tremendous variation; determining acceptable versus worrisome variation is challenging. Screening tests are part of the process of sorting what is probably “normal” from what needs further evaluation before a diagnosis can be made or ruled out. Preventive health care visits are an important time for primary care clinicians to talk with families and perform screening tests, but screening tests are also done at other times. This section provides more information about this monitoring process, as well as more detail about specific screening tests.
The screening and diagnostic process can be direct for certain conditions, but for many families it can be full of twists, turns, and dead-ends. Unfortunately this can be frustrating, time-consuming, and costly. Communication between the family and the Medical Home is important during the entire process, from raising concerns, doing screenings, developing a diagnosis (or ruling out a diagnosis), and following up on a plan of care to adapt it over time.
On this page we will introduce a variety of timelines and processes: from prenatal screening and testing, to newborn and developmental surveillance, screening, and diagnosis. You and your child’s medical home will work together during the screening and follow up processes.

What is a Screening Test?

Screening tests help assess the risk of possible genetic conditions before or during pregnancy, or can draw attention to potential areas of concern surrounding your child’s development after birth. These tests can be done if a concern arises during the process of surveillance (informal observations made by you or by your child’s heath care provider), and on a standard, age-determined schedule. At specific ages, screening tests will be used to gather more data about your child. Often, these screening tests take the form of questionnaires or lab tests that take place at recommended ages. They provide a more-objective way for primary care clinicians to monitor for specific concerns, but screening tests are not the same as diagnostic tests. Diagnostic tests are performed to nail down a diagnosis after a concern arises.
Many tests are used to help identify concerns or risks, or to figure out if a concern needs further evaluation. These screening tests are designed to have “high sensitivity,” meaning that almost all people at risk for a specific condition are identified, and very few people who have that condition are overlooked. In order to make sure that very few people with the condition get missed, screening tests end up identifying some people who don’t actually have the condition (“false positives”), but few affected people test negative. If a person is positively identified during the screening test, he or she will undergo diagnostic testing to determine if he or she actually has the condition (more information on Diagnosis later). Good screening tests have high sensitivity and low cost, so they can be used easily to monitor lots of people at risk for a condition. Prenatal tests, newborn and infant screens, and developmental screening tests are commonly done in Pediatrics. These are discussed in more detail below.

Prenatal Tests

Prenatal tests include tests done before and during pregnancy (see: Prenatal Testing). When planning for a pregnancy, both parents can be tested to find potential genetic conditions that put the mother or fetus at risk for various conditions and outcomes and to help the medical team plan appropriate care for the mother and baby. These screening tests may be done by the primary care clinician, an obstetrics specialist, a genetic counselor, or other related medical professionals. Families can work with genetic counselors to discuss their specific risks for passing along inherited conditions, or having a baby with a genetic condition like Trisomy 21 (Down Syndrome ).
Blood and Urine Tests

During pregnancy, all women will have certain blood and urine screening tests. Blood tests will be used to confirm the pregnancy, determine the mother’s blood type and Rh factor, and determine iron, hemoglobin and glucose levels. These blood tests will be repeated to see if the mother is developing anemia or diabetes during the pregnancy. When testing for diabetes, mothers may be asked to fast (go without food) for a period of time, or they may be given a glucose (sugary) drink before having their blood tested for glucose levels. Uncontrolled diabetes during pregnancy can lead to increased risks for the developing fetus and child, including miscarriage, stillbirth, high blood pressure, breathing difficulties, jaundice, and low blood sugar. Rh Incompatibility can cause jaundice, lethargy, and death. Anemia can lead to low birth weight and premature birth. If the blood tests reveal that a pregnant mother has diabetes, Rh incompatibility, or anemia, she can do certain things, such as taking prescribed medications or modifying her diet during the pregnancy, to help prevent problems for the developing child.
Blood tests may also be used to see if the mother has antibodies to certain diseases, like rubella, or if she has been exposed to sexually transmitted diseases, like HIV, or has infections, like toxoplasmosis. All of these may cause birth defects or other problems for the infant. A certain type of blood test, called an alpha-fetoprotein (AFP) test, screens for some birth defects such as spina-bifida and Down syndrome.
More common than bood tests, urine tests are used to screen for diabetes, urinary tract infections, and pregnancy-induced hypertension (preeclampsia), all of which can affect the baby, and cause great discomfort to the mother.
Ultrasound Exams

Ultrasound (or sonogram) exams are used to view images of the developing fetus. They are used more often in later pregnancy to examine or measure parts of the fetus, such as the head, arms, legs, and heart. Parents may be more familiar with the tests being used to determine the gestational age or sex of the fetus, but there are other types of ultrasound exams that use different equipment, placed in different locations, that can be helpful in identifying structural birth defects, high or low levels of amniotic fluid, and abnormalities in the uterus or placenta. Sometimes, when certain medical problems are suspected, an ultrasound exam will be used to help guide a needle to gather umbilical cord blood for a cordiocentesis, or percutaneous umbilical cord blood sampling (PUBS) test, that can detect infections, blood levels, and malformations.
Chorionic Villus Sampling (CVS) and Amniocentesis Tests

Parents may be referred to a genetic counselor before or during pregnancy to discuss potential risks of passing on genetic conditions and ways of treating known genetic conditions. Many genetic conditions can be found through testing the growing fetus during pregnancy (see: Newborn Disorders). Genetic testing can be done using a few different screening or diagnostic tests. Chorionic villus sampling (CVS) tests cells from the placenta early in pregnancy to diagnose genetic conditions or chromosomal abnormalities such as cystic fibrosis and Down syndrome. Amniocentesis is done later in pregnancy to diagnose some of the same genetic conditions as CVS testing, as well some birth defects that are found in blood test screening. Late in pregnancy, the amniocentesis test can determine if the lungs of the fetus are mature enough before delivery and help doctors determine the best treatment options.
Non-Stress Tests

On or after the 28th week of pregnancy, and during labor, the non-stress test may be used to check fetal movement, heart rate, and contractions. The monitoring is done by attaching belts to the mother’s abdomen to determine if the fetus is reacting well to contractions by watching increases and decreases in movement and heart rate. This test is non-invasive and does not stress the fetus. When an ultrasound exam is combined with a non-stress test, a biophysical profile can be determined, including heart rate, breathing rate, movements, muscle tone, and amniotic fluid levels. If the non-stress test indicates a problem, it may be followed by a stress test, using pitocin to make the uterus contract, so that the doctors can determine if the fetus is having distress and determine the best plan of action.
Group B Strep Test

In the last few weeks of pregnancy, women will be tested for Group B streptococcus (also referred to as beta strep). Group B streptococcus does not always cause symptoms. To see if a woman carries the bacteria, a swab is taken of her vagina and rectum. Those women who test positive (about 1 in 4) will be treated with antibiotics before delivery so that it is not transmitted to the infant during delivery. Infants that are exposed to the Group B streptococcus bacteria can develop an infection that can enter the blood, lungs, and spinal fluid, potentially causing severe complications. It can affect breathing, kidney function, and blood pressure. Infected infants are also treated with antibiotics.

Newborn/Infant Screening

At birth, and shortly afterwards, all infants are checked for hearing problems, genetic conditions, and a number of other chronic conditions. Below you’ll find descriptions of the routine screenings performed on every child.
Blood-Spot Screening

Infants are screened or checked for genetic and chronic conditions using a blood test done two or three times shortly after birth. These tests are sometimes called “newborn screening” or “blood-spot screening” because the tests use a card with five circles of blood spots. The cards are run through machines that look for some fairly common and some rare conditions, such as cystic fibrosis, phenylketonuria (PKU), sickle cell disease, or congenital hypothyroidism (see: Newborn Disorders). It is important to catch these conditions early since they often require life-long treatments and some require special diets. This routine testing does not offer the most accurate or final tests. If a child tests positive for a condition or disease, the clinician will usually order additional, more accurate tests before the primary care clinician can make a diagnosis. Sometimes infants may need to visit a specialist for further examinations or reading of these tests.
Hearing Screening

Newborn infants also have their hearing screened or tested. Since infants are not able to talk or indicate that they can hear, these tests check for nerve responses. The tests, using electronic equipment, can be done while the infant sleeps. For more details, see Universal Newborn Hearing Screening (My Baby's Hearing). Infants who do not “pass” the first screening tests will have more accurate follow-up tests that can better determine if there is any potential hearing impairment. If there is some type of hearing impairment, specialists will be involved in determining what type, if there is a particular cause, and how it will be treated or managed. (See: Hearing Screening).

Developmental Surveillance, Screening, and Diagnosis

Watching a child learn to crawl, walk, and talk can be exciting moments for parents. Medical and child development professionals group these milestones into categories: motor skills include learning to crawl, walk, and hold items; language skills include learning to babble and talk; and cognitive skills include looking, following directions, and counting. These developmental skills eventually help children in daily activities, like playing, interacting with others, and taking care of themselves.
Not every child reaches these milestones at exactly the same age and the “normal range” for reaching them is wide. One child may reach a milestone weeks or months earlier or later than another child and still be within a “normal range.” Some children, however, are much farther behind and have developmental delays. If you have concerns about your child's development, your primary care clinician can check for developmental delays.
The American Academy of Pediatrics (AAP) recommends that pediatricians screen or check the development of every child. [Committee: 2001] These developmental screenings help doctors follow a child’s growth and watch for any “red flags” or early warnings of possible problems. Children with some medical conditions, like attention deficit hyperactivity disorder (ADHD), autism, and cerebral palsy, may have some developmental delays as they grow older. While the diagnosis and treatment differs according to the condition, the developmental screening process is the same for all children. Recognizing delays and acting early may not reverse the delay, but it can help your child gain or keep as much functioning as possible. (For a list of developmental milestones, see: Learn the Signs. Act Early (CDC).) On the rest of this page we will introduce the standard developmental screening processes, from surveillance and developmental screening to assessment and diagnosis. We will also introduce various types of routine medical appointments.

In the context of child development, “surveillance” refers to the flexible and continuous process of asking about a child's growth and watching the child reach milestones (see: Developmental Screening). The primary clinician in the Medical Home (see: About Medical Home) will often ask about feeding, playing, and talking as part of this process. While these questions may seem like everyday conversations, they can offer clues about appropriate development or possible developmental delays. The clinician also directly observes the child as part of this process. “Surveillance” is not the same as “screening,” but the terms are often confused, even by primary care clinicians.
Developmental Screening

Screening is a more formal process of monitoring developmental milestones. The Medical Home team will use tested, standardized screening tools at specific visits to see if the child has reached or missed key milestones. Sometimes, parents fill out the forms for the screening tool. Other times, the nurse or doctor asks questions and fills out the forms. The primary clinician reviews the forms, often with a total score, and decides if the child is developing on schedule or needs a closer look. Screening does not diagnose a developmental delay, but it gives clues if there may be something that needs further testing, assessment, or evaluation.
Some family activities can encourage your child to reach milestones, help him or her grow, and learn new skills, including daily reading and playing. Play helps develop motor, language, and cognitive skills while also helping children use their abundant energy during the day. Daily reading helps develop language and cognitive skills, and for many children it can become part of a relaxing bedtime routine.
Assessment and Evaluation

If a primary clinician notices problems with the developmental screening, he or she will refer the child for further assessment. The assessment and the provider doing the assessment will be specific to the child’s possible problems. A common first step is a referral to a local Early Intervention Part C Program (EI). The EI provider will probably do additional testing, assessments, and interventions to help the child maintain and gain skills. Sometimes, EI providers are also Early Head Start providers, who serve children up to age three. It’s not unusual for children to receive services from Early Intervention or Early Head Start providers before a diagnosis has been determined. The child may also be referred to a developmental pediatrician, who specializes in diagnosing and treating developmental delays. For school-age children, if additional information is needed about school skills, a school psychologist may be involved in the assessment and diagnosis.
When a problem is found or a diagnosis is made, the Medical Home will play an important role in supporting the treatment plan and coordinating care among different providers. The Medical Home will provide treatment or help families find other providers if the developmental delays are mild and there is no diagnosis.
An example of Developmental Surveillance, Screening, and Diagnosis:

Ramon’s mother brings Ramon for his 15-month well child visit. At that visit, Dr. Black asks how many words Ramon can say. Dr. Black observes that Ramon responds to his name and babbles but does not speak any recognizable words. This is developmental surveillance. Dr. Black is a little worried that Ramon has a language delay, because most typically-developing children have started saying words by this age. The physician encourages his mother to read and talk to him a lot over the next 3 months. He also sends Ramon for a hearing test (see: Hearing Tests (My Baby's Hearing)), a diagnostic test meant to rule out hearing loss as the reason Ramon doesn’t speak recognizable words. The results of the test indicate that Ramon hears just fine.

At Ramon’s 18-month well child visit, Dr. Black follows up on his initial concerns and asks Ramon’s parents to fill out forms for two screening tests. One of these is a developmental screening test, such as the Parent's Evaluation of Developmental Status (PEDS), (see: Parent's Evaluation of Developmental Status (PEDS) site) and the other is an autism-specific screening test, such as the (Modified Checklist for Autism in Toddlers – Revised, with Follow-Up (M-CHAT-R/F). After reviewing the information provided by the family, Dr. Black is concerned that Ramon may have a language delay related to an autism spectrum disorder. He then refers Ramon to a psychologist for a diagnostic test for autism spectrum disorders, such as the Autism Diagnostic Observation Schedule (ADOS) test. Ramon’s score on the test reveals that he does not have an autism spectrum disorder. The cognitive testing shows that Ramon does not have intellectual disability or a low IQ. He is diagnosed with an expressive language delay.

Ramon then works with Early Intervention to receive speech and language therapy, and his language skills gradually improve over the next two years. At each subsequent visit, Ramon’s doctor continues to do surveillance by asking questions about Ramon’s development and provides encouragement to the family by noticing the improvements Ramon is making.
Developmental Screening Costs

Developmental screening is part of routine well child care and does not cost families extra. When children need additional assessment or treatment, insurance may cover those costs. For families without insurance, publicly funded services or insurance coverage may be available and the Medical Home may recommend ways that families can help the child maintain or gain skills.

Screening Settings

Screenings are performed in a variety of settings. Prenatal screening is typically done as part of the mother’s prenatal care with a physician or midwife. Newborn and infant screening typically occurs in the hospital and primary care office. Developmental screenings often take place in the Medical Home as part of Well Child Checkups (see below). Children with chronic medical conditions may also have screening done during Chronic Care Visits related to their medical condition (see below). It is common for other community providers to also do developmental screenings and watch for missed milestones. School screenings are an important part of this process (see below). Early Head Start, Head Start, and child care providers may do screenings more often than the Medical Home. Community providers should notify the Medical Home when the screening raises concerns.
School Screenings

In addition to the Medical Home, schools often perform certain screening tests, including hearing, vision, and scoliosis (spine) screening. The types of screening tests that are provided will vary depending upon the rules set by state legislatures and school boards. Depending upon the state and the specific screening test, parents may need to provide a signed consent form for their child to have a screening test. For example, a scoliosis screening test will usually require parental consent since it involves the child removing his or her shirt to check for curvatures in the spine as the child bends over.
School nurses or volunteers may help provide the screening tests and refer concerns about the test results to the child’s Medical Home. The relatively inexpensive tools used for these screening tests are usually designed to provide basic testing. For example, a vision screening may use a wall chart with basic shapes, rather than specialized equipment that would be found in an ophthalmologist’s office. Hearing screening tests are often done in a quiet location, but not in a sound-proof booth, and a child is simply asked to indicate when he or she hears different tones by raising a hand. Again, these tests do not diagnose a medical condition, but they can help identify children who may need a closer look or further evaluation by specialists using more sensitive equipment.
Well Child Checkups

Well child checkups are appointments for children of all ages during which primary care clinicians will determine if children are on track for growth and development. These visits are scheduled for certain ages, with more frequent visits for infants, and yearly visits for older children and teenagers (see: 2020 Bright Futures Periodicity Schedule (AAP) (PDF Document 119 KB)). Parents need to take their children to these well child checkups even if their child has been to a physician or other clinics for sicknesses.
During each visit, the child's height and weight will be measured and recorded on growth charts. Immunizations will be given at the right ages, according to a standardized schedule (see: Childhood Immunization Schedule (Utah)). Hearing, vision, lead, developmental, autism, and other screening tests will be done at appropriate ages. The primary care clinician will also ask about age-appropriate development, such as learning to talk for young children or sexual maturation for teenagers. These visits also provide time for parents to ask about their child’s health and behavior, and for the Medical Home to teach parents about child safety issues, such as the proper use of car seats and bike helmets, or to discuss issues surrounding the use of harmful drugs.
Chronic Care Visits

Children that have a chronic medical condition, such as diabetes, cerebral palsy, asthma, autism, or bipolar disorder, will need to visit their Medical Home more frequently than the usual well child visits. These chronic care visits are regularly-scheduled visits in addition to acute care visits for illnesses or unexpected problems. Children will still need to have well child visits to screen for other problems and get vaccinations at the right ages.
The Medical Home will usually schedule additional time for chronic care visits since the primary care clinician will spend more time with the child for tests, physical evaluations, medication reviews, and teaching (anticipatory guidance). For example, during a chronic care visit for a child with diabetes, the primary care clinician will need more time to check blood glucose levels, examine the child for sores, review insulin prescriptions, and teach about insulin pumps. If the parents change to a new Medical Home, they should request longer appointments until the Medical Home gets into the routine of automatically scheduling them.


Information & Support

For Parents and Patients

Prenatal Testing
List and description of various tests from the American Pregnancy Association.

Learn the Signs. Act Early (CDC)
Offers many tools, videos, lists, learning materials, and an app to track a child’s developmental milestones (ages 2 months to 5 years) and act if concerned about progress; Centers for Disease Control and Prevention.

Learn the Signs. Act Early. Tools
Checklists, booklets, and other tools to learn about and track developmental milestones for infants and young children.

Developmental Screening (CDC)
Written for families, this resource provides an overview of screening, the pros and cons of screening tools, links to federal resources; Centers for Disease Control and Prevention.

Early Developmental Guide for Parents
From the Utah Department of Health, a list of milestones for ages 1-2 months, 3-4 months, 6 months, 9 months, 12 months, 18 months, 2-3 years. Includes development, nutrition, communication/hearing/vision, and guidance for parents

Parenting (Zero to Three)
A webpage from the Zero to Three national, nonprofit organization dedicated to supporting families and communities in the care of young children. This site has links to FAQs; parenting tips; and reproducible handouts for parents. Topics include behavior, sleep, play, language, and more.

Parent's Guide to Understanding Subspecialists
An American Academy of Pediatrics webpage that links to information about pediatric subspecialists and transport teams. Includes guidelines for referral to pediatric surgical specialists.

Utah Parent Center
A nonprofit organization that provides training, information, referral, and assistance to parents of children and youth with all disabilities including physical, mental, hearing, vision, learning, behavioral, and emotional. Staff consists primarily of parents of children and youth with disabilities.

Baby Watch Referral Form (PDF Document 156 KB)
Information referral and release form to exchange information between the Medical Home and early intervention programs in Utah.

Rh Incompatibility
Explanation of the condition from Medline Plus.

Hearing Tests (My Baby's Hearing)
Overview of hearing testing in children; Boys Town National Research Hospital.

Parent's Evaluation of Developmental Status (PEDS) site
PEDS and PEDS:DM provide 5-minute screenings, longitudinal surveillance, and triage for developmental as well as behavioral/social-emotional/mental health problems. Can be completed by parent self-report, interview, or administered directly to children; available for a fee.

M-CHAT (Modified Checklist for Autism in Toddlers) (PDF Document 117 KB)
The M-CHAT is copyrighted, and its use must follow these guidelines: (1) Reprints/reproductions of the M-CHAT must include the copyright (© 1999 Robins, Fein, & Barton). No modifications can be made to items or instructions without permission. (2) It must be used in its entirety. (3) Parties interested in reproducing the M-CHAT in print (e.g., a book or journal article) or electronically (e.g., as part of digital medical records or software packages) must contact Diana Robins to request permission ( More information is available at,_Ph.D..html.

Childhood Immunization Schedule (Utah)
English and Spanish versions of recommended shots for infants, toddlers, and young children.

Building Your Care Notebook (AAP)
The American Academy of Pediatrics provides a central place with links to several forms from many states. For families that are new to making care notebooks, we suggest you pick one form and try filling it out before downloading other forms.

Collaborative Care Notebook (PDF Document 467 KB)
From Utah Family Voices, this care notebook in PDF format incorporates forms from many other states. Use selected pages or the entire notebook.

Completo Care Notebook (PDF Document 1.3 MB)
En Espanol.

Tips on setting up your care notebook (PDF Document 191 KB)

Services for Patients & Families in Utah (UT)

For services not listed above, browse our Services categories or search our database.

* number of provider listings may vary by how states categorize services, whether providers are listed by organization or individual, how services are organized in the state, and other factors; Nationwide (NW) providers are generally limited to web-based services, provider locator services, and organizations that serve children from across the nation.

Authors & Reviewers

Initial publication: October 2013
Current Authors and Reviewers:
Authors: Alfred N. Romeo, RN, PhD
Lynne M. Kerr, MD, PhD
Jennifer Goldman-Luthy, MD, MRP, FAAP

Page Bibliography

Committee on Children with Disabilties.
Developmental surveillance and screening of infants and young children.
Pediatrics. 2001;108(1):192-6. PubMed abstract / Full Text
This article encourages physicians to use standardized developmental screening tools and suggests that testing children at periodic intervals will increase accuracy and further early intervention.