Autism Diagnostic Observation Schedule Explained

Autism Diagnostic Observation Schedule
Purpose:assess autism in children, adolescents, and adults

The Autism Diagnostic Observation Schedule (ADOS) is a standardized diagnostic test for assessing autism spectrum disorder. The protocol consists of a series of structured and semi-structured tasks that involve social interaction between the examiner and the person under assessment. The examiner observes and identifies aspects of the subject's behavior, assigns these to predetermined categories, and combines these categorized observations to produce quantitative scores for analysis. Research-determined cut-offs identify the potential diagnosis of autism spectrum disorder, allowing a standardized assessment of autistic symptoms.

The Autism Diagnostic Interview-Revised (ADI-R), a companion instrument, is a structured interview conducted with the parents of the referred individual to cover the subject's full developmental history. The ADI-R has lower sensitivity but similar specificity to the ADOS.

History

The original ADOS was created by Catherine Lord, Michael Rutter, Pamela C. DiLavore and Susan Risi in 1989.[1]

PL-ADOS

Responding to the need for diagnostic tools for autism in younger children, researchers developed the Pre-Linguistic Autism Diagnostic Observation Schedule (PL-ADOS).[2] The content of the activities, as well as the general format, were adapted to rely less on conversation.

ADOS-G

In 2000, Lord and her colleagues introduced the ADOS-Generic (ADOS-G) as a means to assess a broader developmental range of individuals. The ADOS-G introduced a module format, allowing for different protocols to be used depending on developmental and language factors.[3] It became commercially available in 2001 through Western Psychological Services.[4]

ADOS-2

A second edition was published in 2012 to include updated norms, improved algorithms for Modules 1 to 3, and a new Toddler Module (T) that facilitates assessment in children ages 12 to 30 months.[5] [6] Changes were also made to the algorithm to report on domains more in line with the recent changes to diagnostic criteria in the DSM-5. Whereas the ADOS-G determined social, communication, and social-communication domains, the ADOS-2 combined these domains to represent social affect, and added a new domain to assess restrictive and repetitive behaviors (RRB).

Method

The ADOS consists of a series of structured and semi-structured tasks that generally takes 30-60 minutes to administer. During this time, the examiner provides a series of opportunities for the subject to show social and communication behaviors relevant to the diagnosis of autism.[4] Each subject is administered activities from the module that corresponds to their developmental and language level. The ADOS should not be used for formal diagnosis with individuals who are blind, deaf, or otherwise seriously impaired by sensory or motor disorders, such as cerebral palsy or muscular dystrophy.

Following task administration and observation coding, a scoring algorithm classifies the individual with autism, autism spectrum disorder, or non-spectrum disorder. The toddler module algorithm yields a "range of concern" rather than a definite classification.[7]

Modules

Toddler module

The toddler module is appropriate for children 12–30 months who use little to no phrase speech. Because social communication and behavioral patterns can be highly variable in the first 2 years of life, the toddler module is typically used to identify areas for continued monitoring rather than to provide a definite diagnosis. The toddler must be able to walk independently.[8] This module consists of eleven primary activities:[7]

  1. Free play
  2. Blocking toy play
  3. Response to name
  4. Bubble play
  5. Anticipation of a routine with objects
  6. Response to joint attention
  7. Responsive social smile
  8. Anticipation of social routine
  9. Functional and symbolic imitation
  10. Bath time
  11. Snack

Module 1

Module 1 is appropriate for children 31 months and older who use little or no phrase speech. This module consists of ten activities:[5]

  1. Free play
  2. Response to name
  3. Response to joint attention
  4. Bubble play
  5. Anticipation of a routine with objects
  6. Responsive social smile
  7. Anticipation of a social routine
  8. Functional and symbolic imitation
  9. Birthday party
  10. Snack

Module 2

Module 2 is appropriate for children six years old or younger who speak in phrases but have not yet developed fluent verbal language. This module consists of fourteen activities:[5]

  1. Construction task
  2. Response to name
  3. Make-believe play
  4. Joint interactive play
  5. Conversation
  6. Response to joint attention
  7. Demonstration task
  8. Description of a picture
  9. Telling a story from a book
  10. Free play
  11. Birthday party
  12. Snack
  13. Anticipation of a routine with objects
  14. Bubble play

Module 3

Module 3 is appropriate for children or young adolescents who are verbally fluent. This module consists of fourteen activities:[5]

  1. Construction task
  2. Make-believe play
  3. Joint interactive play
  4. Demonstration task
  5. Description of a picture
  6. Telling a story from a book
  7. Cartoons
  8. Conversation and reporting
  9. Emotions
  10. Social difficulties and annoyance
  11. Break
  12. Friends, relationships, and marriage
  13. Loneliness
  14. Creating a story

Module 4

Module 4 is appropriate for older adolescents and adults. While similar to module 3, module 4 relies more heavily on questions and verbal responses rather than non-verbal actions observed during play. This module consists of ten to fifteen activities. Activities marked by an asterisk are optional:

  1. Construction task*
  2. Telling a story from a book
  3. Description of picture*
  4. Conversation and reporting
  5. Current work or school*
  6. Social difficulties and annoyance
  7. Emotions
  8. Demonstration task
  9. Cartoons*
  10. Break
  11. Daily living*
  12. Friends, relationships, and marriage
  13. Loneliness
  14. Plans and hopes
  15. Creating a story

Diagnostic accuracy

The social communication difficulties that the ADOS and ADOS-2 seek to measure are not unique to ASD; there is a heightened risk of false positives in individuals with other psychological disorders. In particular, an increased false positive rate has been observed in adults with psychosis;[9] while case reports indicate that such false positives may also occur in cases of childhood-onset schizophrenia, which is an exceptionally rare entity with a frequency of 1 in 40000.[10] There is evidence that adults with schizophrenia demonstrate an increased incidence of autistic features compared to the general population, resulting in higher ADOS scores, though schizophrenia patients also experience positive symptoms of psychosis (e.g. hallucinations, delusions, formal thought disorders).[11] [12] A 2016 study found that 21% of children with a diagnosis of ADHD (and without a concurrent diagnosis of ASD) scored in the autism spectrum range on the ADOS total score.[13]

A 2018 Cochrane systematic review included 12 studies of ADOS diagnostic accuracy in pre-school children (Modules 1 and 2). The summary sensitivity was 0.94 (95% CI 0.89 to 0.97), with sensitivity in individual studies ranging from 0.76 to 0.98. The summary specificity was 0.80 (95% CI 0.68 to 0.88), with specificity in individual studies ranging from 0.20 to 1.00. The studies were evaluated for bias using the QUADAS-2 framework; of the 12 included studies, 8 were evaluated as having a high risk of bias, while for the remaining four there was insufficient information available for the risk of bias to be properly evaluated. The authors could not identify any studies for the ADOS-2; the scope of the review was limited to preschool age children (mean age under 6 years), which excluded studies of Modules 3 and 4 from the meta-analysis. One included study examined the additive sensitivity and specificity of the ADOS used in combination with the ADI-R; that study found an 11% improvement in specificity (compared to ADOS alone) at the cost of a 14% reduction in sensitivity; however, due to overlapping confidence intervals, that result could not be considered statistically significant.[14]

Further reading

External links

Notes and References

  1. "Autism Diagnostic Observation Schedule." Western Psychological Services. Western Psychological Services. n.d. Web. 6 March 2010.
  2. DiLavore . P . Lord . C . Rutter . M . 1995 . Pre-Linguistic Autism Diagnostic Observation Schedule (PL-ADOS). . Journal of Autism and Developmental Disorders . 25 . 4 . 355-379.
  3. Lord . C . Risi . S . Lambrecht . L . Cook, Jr . E H . Leventhal . B L . DiLavore . P C . Pickles . A . Rutter . M . 2000 . The Autism Diagnostic Observation Schedule–Generic: A Standard Measure of Social and Communication Deficits Associated with the Spectrum of Autism. . Journal of Autism and Developmental Disorders . 30 . 3 . 205-223 . 10.1023/A:1005592401947 . 11055457.
  4. Akshoomoff . Natacha . Corsello . Christina . Schmidt . Heather . The Role of the Autism Diagnostic Observation Schedule in the Assessment of Autism Spectrum Disorders in School and Community Settings . The California School Psychologist . Springer Science and Business Media LLC . 11 . 1 . 2006 . 1087-3414 . 10.1007/bf03341111 . 7–19 . 1868476 . 17502922 .
  5. Lord C, DiLavore PC, Gotham K, Guthrie W Luyster RJ, Risi S, Rutter M. Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) Manual. Torrance, CA: Western Psychological Services; 2012.
  6. Lord C, Luyster R, Gotham K, Guthrie W. Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) Manual (Part II): Toddler Module. Torrance, CA: Western Psychological Services; 2012.
  7. McCrimmon . Adam . Rostad . Kristin . February 2014 . Test Review: Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) Manual (Part II): Toddler Module . Journal of Psychoeducational Assessment . en . 32 . 1 . 88–92 . 10.1177/0734282913490916 . 145257612 . 0734-2829.
  8. Esler . Amy N. . Bal . Vanessa Hus . Guthrie . Whitney . Wetherby . Amy . Weismer . Susan Ellis . Lord . Catherine . September 2015 . The Autism Diagnostic Observation Schedule, Toddler Module: Standardized Severity Scores . Journal of Autism and Developmental Disorders . en . 45 . 9 . 2704–2720 . 10.1007/s10803-015-2432-7 . 25832801 . 4898775 . 0162-3257.
  9. Maddox BB, Brodkin ES, Calkins ME, Shea K, Mullan K, Hostager J, Mandell DS, Miller JS . The Accuracy of the ADOS-2 in Identifying Autism among Adults with Complex Psychiatric Conditions . Journal of Autism and Developmental Disorders . 47 . 9 . 2703–2709 . September 2017 . 28589494 . 5813679 . 10.1007/s10803-017-3188-z .
  10. Reaven JA, Hepburn SL, Ross RG . Use of the ADOS and ADI-R in children with psychosis: importance of clinical judgment . Clinical Child Psychology and Psychiatry . 13 . 1 . 81–94 . January 2008 . 18411867 . 4426195 . 10.1177/1359104507086343 .
  11. Barlati S, Deste G, Gregorelli M, Vita A . Autistic traits in a sample of adult patients with schizophrenia: prevalence and correlates . Psychological Medicine . 49 . 1 . 140–148 . January 2019 . 29554995 . 10.1017/S0033291718000600 . 4020382 .
  12. De Crescenzo F, Postorino V, Siracusano M, Riccioni A, Armando M, Curatolo P, Mazzone L . Autistic Symptoms in Schizophrenia Spectrum Disorders: A Systematic Review and Meta-Analysis . Frontiers in Psychiatry . 10 . 78 . 2019-02-21 . 30846948 . 6393379 . 10.3389/fpsyt.2019.00078 . free .
  13. Grzadzinski R, Dick C, Lord C, Bishop S . Parent-reported and clinician-observed autism spectrum disorder (ASD) symptoms in children with attention deficit/hyperactivity disorder (ADHD): implications for practice under DSM-5 . Molecular Autism . 7 . 1 . 7 . December 2016 . 26788284 . 4717584 . 10.1186/s13229-016-0072-1 . free .
  14. Randall M, Egberts KJ, Samtani A, Scholten RJ, Hooft L, Livingstone N, Sterling-Levis K, Woolfenden S, Williams K . Diagnostic tests for autism spectrum disorder (ASD) in preschool children . The Cochrane Database of Systematic Reviews . 2018 . CD009044 . July 2018 . 7 . 30075057 . 6513463 . 10.1002/14651858.CD009044.pub2 . Cochrane Developmental, Psychosocial and Learning Problems Group .