A Multi-Tiered Approach to Screening for Autism in Schools
There has been a worldwide increase in the prevalence of autism over the past decade. Yet, compared to population estimates, identification rates have not kept pace in our schools. It is not unusual for children with less severe symptoms of autism spectrum disorder (ASD) to go unidentified until well after entering school. As a result, it is critical that school-based support personnel (e.g., school psychologists, special educators, school counselors, speech/language pathologists, and social workers) give greater priority to case finding and screening to ensure that children with ASD are identified and have access to the appropriate programs and services.
Screening and Identification
Until recently, there were
few validated screening measures available to assist school professionals in
the identification of students with the core ASD-related behaviors. However,
our knowledge base is expanding rapidly and we now have reliable and valid
tools to screen and evaluate children more efficiently and with greater
accuracy. The following tools have demonstrated utility in screening for ASD in
educational settings and can be used to determine which children are likely to
require further assessment and/or who might benefit from additional support.
All measures have sound psychometric properties,
are appropriate for school-age children, and time efficient (10 to 20 minutes
to complete). Training needs are minimal and require little or no professional
instruction to complete. However, interpretation of results requires
familiarity with ASD and experience in administering, scoring, and interpreting
psychological tests.
The Autism Spectrum Rating Scales (ASRS;
Goldstein & Naglieri, 2009) is a norm-referenced tool designed to
effectively identify symptoms, behaviors, and associated features of ASD in
children and adolescents from 2
to 18 years of age. The ASRS can be completed by teachers and/or parents and
has both long and short forms. The Short form was developed for screening
purposes and contains 15 items from the full-length form that have been shown
to differentiate children diagnosed with ASD from children in the general
population. High scores indicate that many behaviors associated with ASD have
been observed and follow-up recommended.
The Social Communication Questionnaire (SCQ; Rutter,
Bailey, & Lord, 2003), previously known as the Autism Screening
Questionnaire (ASQ), is a parent/caregiver dimensional measure of ASD
symptomatology appropriate for children of any chronological age older than
four years. It is available in two forms, Lifetime and Current, each with 40
questions. Scores on the questionnaire provide a reasonable index of symptom
severity in the reciprocal social interaction, communication, and
restricted/repetitive behavior domains and indicate the likelihood that a child
has an ASD. The lifetime version is recommended for screening
purposes as it demonstrates the highest sensitivity value.
The Social Responsiveness Scale, Second Edition (SRS-2; Constantino & Gruber, 2012)
is a brief quantitative measure of autistic behaviors in 4 to 18 year old
children and youth. This 65-item rating scale was designed to be completed by
an adult (teacher and/or parent) who is familiar with the child’s current
behavior and developmental history. The SRS items measure the ASD symptoms in
the domains of social awareness, social information processing, reciprocal
social communication, social anxiety/avoidance, and stereotypic
behavior/restricted interests. The scale provides a Total Score that reflects
the level of severity across the entire autism spectrum.
A Multi-Tier Screening
Strategy
The ASRS, SCQ,
and SRS-2 can be used confidently as efficient first-level screening
tools for identifying the presence of the more broadly defined and subtle
symptoms of higher-functioning ASD in school settings. School-based
professionals should consider the following multi-step strategy for identifying
at-risk students who are in need of an in-depth assessment.
Tier one. The initial step is case finding.
This involves the ability to recognize the risk factors and/or warning signs of
ASD. All school professionals should be engaged in case finding and be alert to
those students who display atypical social and/or communication behaviors that
might be associated with ASD. Parent and/or teacher reports of social
impairment combined with communication and behavioral concerns constitute a
“red flag” and indicate the need for screening. Students who are identified
with risk factors during the case finding phase should be referred for formal
screening.
Tier two. Scores on the ASRS, SCQ,
and SRS-2 may be used as an indication of the approximate severity of
ASD symptomatology for students who present with elevated developmental risk
factors and/or warning signs of ASD. Screening results are shared with parents
and school-based teams with a focus on intervention planning and ongoing
observation. Scores can also be used for progress monitoring and to measure
change over time. Students with a positive screen who continue to show minimal
progress at this level are then considered for a more comprehensive assessment
and intensive interventions as part of Tier 3.
However, as with all screening tools, there will be some false negatives
(children with ASD who are not identified). Thus, children who screen negative,
but who have a high level of risk and/or where parent and/or teacher concerns
indicate developmental variations and behaviors consistent with an
autism-related disorder should continue to be monitored, regardless of
screening results.
Tier three. Students who
meet the threshold criteria in step two may then referred for an in-depth
assessment. Because the ASRS, SCQ, and SRS-2 are strongly
related to well-established and researched gold standard measures and report high
levels of sensitivity (ability to correctly identify cases in a population),
the results from these screening measures can be used in combination with a
comprehensive developmental assessment of social behavior, language and
communication, adaptive behavior, motor skills, sensory issues, and cognitive
functioning to aid in determining eligibility for special education services
and as a guide to intervention planning.
Limitations
Concluding Comments
Although the ASRS, SCQ, and SRS can be used
confidently as efficient screening tools for identifying children across the
broad autism spectrum, they are not without limitations. Some students who
screen positive will not be identified with an ASD (false positive). On the
other hand, some children who were not initially identified will go on to meet
the diagnostic and/or classification criteria (false negative). Therefore, it
is especially important to carefully monitor those students who screen negative
to ensure access to intervention services if needed. Gathering information from
family and school resources during screening will also facilitate
identification of possible cases. Autism specific tools are not currently
recommended for the universal screening of typical school-age children. Focusing
on referred children with identified risk-factors and/or developmental delays
will increase predictive values and result in more efficient identification
efforts.
Compared with general
population estimates, children with mild autistic traits appear to be an
underidentified and underserved population in our schools. There are likely a
substantial number of children with equivalent profiles to those with a
clinical diagnosis of ASD who are not receiving services. Research indicates that
outcomes for children on the autism spectrum can be significantly enhanced with
the delivery of intensive intervention services. However, intervention services can only be implemented if students are
identified. Screening is the initial step in this process. School professionals
should be prepared to recognize the presence of risk factors and/or early
warning signs of ASD, engage in case finding, and be familiar with screening
tools in order to ensure children with ASD are being identified and provided
with the appropriate programs and services.
Best practice screening and assessment guidelines are available from: Autism Spectrum Disorder in Children and Adolescents: Evidence-Based Assessment and Intervention in Schools and A Best Practice Guide to Assessment and Intervention for Autism Spectrum Disorder in Schools (2nd ed.).
Best practice screening and assessment guidelines are available from: Autism Spectrum Disorder in Children and Adolescents: Evidence-Based Assessment and Intervention in Schools and A Best Practice Guide to Assessment and Intervention for Autism Spectrum Disorder in Schools (2nd ed.).
Lee A.
Wilkinson, PhD, is a
licensed and nationally certified school psychologist, and certified cognitive-behavioral
therapist. He is author of the award-winning books, A
Best Practice Guide to Assessment and Intervention for Autism and Asperger
Syndrome in Schools and Overcoming
Anxiety and Depression on the Autism Spectrum: A Self-Help Guide Using CBT. He
is also editor of a text in the APA School Psychology Book
Series, Autism
Spectrum Disorder in Children and Adolescents: Evidence-Based Assessment and
Intervention in Schools. His latest book is A
Best Practice Guide to Assessment and Intervention for Autism Spectrum Disorder
in Schools (2nd Edition)