Exams and Tests
The American Academy of Pediatrics
(AAP) recommends screening children for
autism during regularly scheduled
well-child visits. This policy helps doctors identify
signs of autism early in its course. Early diagnosis and treatment can help the
child reach his or her full potential.
When a developmental delay
is recognized in a child, further testing can help a doctor determine whether
the problem is related to autism, another
pervasive developmental disorder (PDD), or a
condition with similar symptoms, such as
language delays or
avoidant personality disorder. If your primary care
provider does not have specific training or experience in developmental
problems, he or she may refer your child to a specialist—usually a
developmental pediatrician, psychiatrist, speech therapist, or child
psychiatrist— for the additional testing.
- Behavioral assessments.
Various guidelines and questionnaires are used to help a doctor determine the
specific type of developmental delay a child has. These include:2
- Medical history. During the medical
history interview, a doctor asks general questions about a child's development,
such as whether a child shows parents things by pointing to objects. Young
children with autism often point to items they want, but do not point to show
parents an item and then check to see if parents are looking at the item being
pointed out.
- Diagnostic guidelines for autism. The American
Association of Childhood and Adolescent Psychiatry (AACAP) has established
guidelines for diagnosing
autism.2 The criteria are
designed so a doctor can assess a child's behavior relating to core symptoms of
autism. The criteria are designed for children age 3 and
older.
- Other
behavioral questionnaires. Additional diagnostic tests
focus on children younger than age 3.
- Clinical observations. A
doctor may want to observe the developmentally delayed child in different
situations. The parents may be asked to interpret whether certain behaviors are
usual for the child in those circumstances.
- Developmental and
intelligence tests. The AACAP also recommends that tests be given to evaluate
whether a child's developmental delays affect his or her ability to think and
make decisions.
- Physical assessments and
laboratory tests. Other tests may be used to determine whether a
physical problem may be causing symptoms. These tests include:
- Physical examination, including head
circumference, weight, and height measurements, to determine whether the child
has a normal growth pattern.
- Hearing
tests, to determine whether hearing problems may be causing
developmental delays, especially those related to social skills and language
use.
- Testing for lead poisoning, especially if a condition
called
pica (in which a person craves substances that are not
food, such as dirt or flecks of old paint) is present. Children with
developmental delays usually continue putting items in their mouth after this
stage has passed in normally developing children. This practice can result in
lead poisoning, which should be identified and treated as soon as
possible.
Additional laboratory tests may be done under specific
circumstances. These tests include:
- Chromosomal analysis, which may be done
if mental retardation is present or there is a family history of mental
retardation. For example, fragile X syndrome, which causes a range of
below-normal intelligence problems as well as autistic-like behaviors, can be
identified with a chromosomal analysis.
- An
electroencephalograph (EEG), which is done if there
are symptoms of seizures, such as a history of staring spells or if a person
reverts to less mature behavior (developmental regression).
- A
magnetic resonance image (MRI), which may be done if
there are signs of differences in the structure of the brain.
Early detection
All doctors who see infants and
children for well-child visits should watch for early signs of developmental
disorders.
Developmental screening tools, such as the Ages and
Stages Questionnaire or the Modified Checklist for Autism in Toddlers (M-CHAT),
can help assess behavior.
If a doctor discovers the following
obvious signs of developmental delays, the child should immediately be
evaluated:4
- No babbling, pointing, or other gestures by
12 months
- No single words by 16 months
- No 2-word
spontaneous phrases by 24 months, with the exception of repeated phrases
(echolalia)
- Any loss of any language or
social skills at any age
If there are no obvious signs of developmental delays or
any unusual indications from the screening tests, most infants and children do
not need further evaluation until the next well-child visit.
But
children who have a sibling with autism should continue to be closely
monitored, because they are at increased risk for autism and other
developmental problems. In addition to the evaluations at well-child visits,
these children should undergo testing for language delays, learning problems,
poor socialization skills, and any symptoms that might suggest they have
anxiety or
depression.4
When socialization, learning, or behavior problems develop in a person at
any time or at any age, he or she should also be evaluated.