Gilliam Autism Rating Scale Second Edition

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Gilliam Autism Rating Scale Second Edition

• Eric Rozenblat, M.A., BCBA
• Caldwell College
• Assessment Project

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Overview

• Background of GARS II
• Changes from original GARS to GARS II
• Peer-reviewed literature about GARS
• Description/Administration of GARS II
• Scoring of GARS II
• Pros and Cons about GARS II
• Recommended Usages

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Background of GARS

• Originally published in 1995 (Gilliam, 1995)
• Based on definition of autism in DSM IV and
  Autism Society of America (1994)
• Reliable and valid standardized test
• Goal of GARS
• Tests for reliability
• Tests for validity
• Used in schools and clinics internationally

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Background of GARS

• 56-items divided into 4 subscales
• Stereotyped Behaviors
• Communcation
• Social Interaction
• Developmental Disturbances
• Autism Quotient Scores and probability of having
  autism
• Below 69 very low
• 70-79 low
• 80-89 below average
• 90-110 average
• 111-120 above average
• 120-130 high
• 131 very high

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Revisions from original GARS

• Development Disturbances subscale converted into
  interview
• Re-written items
• Demographic characteristics
• New norms created
• Autism Index
• Guidelines for scores
• Discrete target behaviors
• Instructional Objectives for Children Who Have
  Autism

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South et al. (2002)

• The purpose of the South et al. study
  investigated the validity of using the GARS (1st
  edition) for children with pre-exisisting
  diagnoses of autism.
• Examined GARS data for 119 children
• Results showed mean GARS IQ was 90.10
• Developmental Disturbances subscale not
  coorelated
• Limitation

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Lecavalier (2005)

• Purpose was to examine construct and diagnostic
  validity, interrater reliability, and effects of
  participant characteristics on GARS scores

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Lecavalier (2005)

• 29 school districts across Ohio
• Children selected between 3-21 who receive
  educational services for ASDs
• Data collected from parents and teacher
• Final analysis included two components
• Possess minimal language skills, expressive
  language at or above 20-month level
• Minimum raw score

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Lecavilier (2005)

• Verify information
• Parents asked if their child had been diagnosed
  by physician or psychologist as having an ASD
  and
• Teachers reported students classification as
  noted in their IEP
• Final sample
• 284 students, 225 male, 47 female, 12 no gender
• 195 autism, 35 pre-k disability, 29 misc, 25 none

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Lecavilier (2005) Results

• Three factor analysis for construct validity
• Factor 1-Stereotyped Behavior
• One item did not belong, 7 others did from 2
  subscales
• Factor 2-Communication
• All but 3 within communication belonged
• Factor 3-Social Interaction
• No items coorelated
• No statistical differences on three behavioral
  subscales
• No statistical difference between teacher/parent
  ratings

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Other References

• Eaves 2006-reliability and validity of GARS
• Results supported use of GARS as screening tool

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DSM-IV-TR

• Important to consider Diagnostic Criteria of
  Autism in DSM-IV-TR
• A total of six or more items from 1, 2, and 3
  with at least 2 from 1 and one each from 2 and 3
• Qualitative impairment in social interaction
• Qualitiative impairment in communication
• Restricted and repetitive stereotyped patterns of
  behavior

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Description/Administration of GARS II

• 42 clearly stated items divided into three
  subscales
• Parent Interview
• Most current definitions
• Normed scale on 1,107 representatives
• Objective
• 5-10 min to administer

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Description/Administration of GARS II

• Three subscales with 14 items each
• Stereotyped Behaviors
• Example includes rocks back and forth
• Communication
• Example includes repeats words or phrases over
  and over
• Social Interaction
• Example includes avoids eye contact
• Examiner/Rater Qualifications

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Scoring Presentation

• Tables A-1 and A-2

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Normative Data

• See table 4.1

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Reliability and Validity

• See back of test

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GARS II and ABA

• See Chapter 7 in Examiner Book and Instructional
  Objectives for Children Who Have Autism

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PROS and CONS

• Pros Cons
• Easy to administer GARS II not enough to DX
• Takes little time Anecdotal parent
  questionnaire
• Good reliability Lack of peer-reviewed research
  on GARSII
• Good validity Raters may be subjective
• Easy to compute Examiner may not administer
  test on own
• Relation to ABA Does not describe environmental
  contingencies
• Direct Observation Examiner qualifications
  (need specialists in autism with license)
• Easy to score
• Uses DSM IV Definition
• Large Normative Sample

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Recommended Usages

• Eaves et al. (2006)
• The analysis of the internal consistency of the
  GARS supported its use as a screening device
• California Collaborative Work Group on Autism
  Spectrum Disorders (1997)
• The Quality Standards Subcommittee of the
  American Academy of Neurology
• The Child Neurology Center (Filipek et al. 2000)

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Recommended Usages

• Recommended not as primary measure
• Autism specialists
• Interpret with skepticism

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Questions
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References

• American Psychiatric Association. (1994).
  Diagnostic and statistical manual of mental
  disorders (4th ed., text rev.). Washington, DC
  Author.
• Boggs, K.M., Gross, A.M., Gohm, C.L. (2006).
  Validity of the Asperger Syndrome Diagnostic
  Scale. Journal of Developmental and Physical
  Disabilities, 18, 163-182.
• Bruininks, R.H., Woodcock, R.W., Weatherman,
  R.F., Hill, B.K. (1996). Scales of independent
  behavior-Revised Manual. Boston Riverside
  Publishing Company.
• California Departments of Education and
  Developmental Services Collaborative Work Group
  on Autism Spectrum Disorders. (1997). Best
  practices for designing and delivering effective
  programs for individuals with autistic spectrum
  disorders. Available online at www.feat.org.
• Eaves, R.C., Woods-Groves, S., Williams Jr.,
  T.O., Fall, A.M. (2006). Reliability and
  validity of the pervasive developmental disorders
  rating scale and the gilliam autism rating scale.
  Education and Training in Developmental
  Disabilities, 41, 300-309.

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References

• Filipek, P.A., Accardo, P.J., Baranek, G.T.,
  Cook, E.H., Dawson, G. et al. (1999). The
  screening and diagnosis of autism spectrum
  disorders. Journal of Autism and Developmental
  Disorders, 29, 439-484.
• Gilliam, J.E. (2006). Gilliam Autism Rating
  Scale. (2nd ed.). Austin, TX PRO-ED.
• Gilliam, J.E. (1995). Gilliam Autism Rating
  Scale. Austin, TX PRO-ED.
• Lecavalier, L. (2005). An evaluation of the
  gilliam autism rating scale. Journal of Autism
  and Developmental Disorders, 35, 795-805.
• Lopez, B.R., Lincoln, A.J., Ozonoff, S., Lai,
  Z. (2005). Examining the relationship between
  executive functions and restricted, repetitive
  symptoms of autistic disorder. Journal of Autism
  and Developmental Disorders, 35, 445-460.
• South, M., Williams, B.J., McMahon, W.M., Owley,
  T., Filipek, P.A., Shernoff, E., Corsello, C.,
  Lainhart, J.E., Landa, R., Ozonoff, S. (2002).
  Utility of the gilliam autism rating scale in
  research and clinical populations. Journal of
  Autism and Developmental Disorders, 32, 593-599.
• Walz, N.C. (2007). Parent reports of stereotyped
  behaviors, social interaction, and developmental
  disturbances in individuals with angelman
  syndrome. Journal of Autism and Developmental
  Disorders, 37, 940-947.