Gilliam Autism Rating Scale Second Edition

1. Gilliam Autism Rating Scale Second Edition Eric Rozenblat, M.A., BCBA Caldwell College Assessment Project

2. 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

3. 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

4. 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

5. 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

6. 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

7. Lecavalier (2005) • Purpose was to examine construct and diagnostic validity, interrater reliability, and effects of participant characteristics on GARS scores

8. Lecavalier (2005) • 29 school districts across Ohio • Children selected between 3-21 who receive educational services for ASD’s • 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

9. 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

10. 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

11. Other References • Eaves 2006-reliability and validity of GARS • Results supported use of GARS as screening tool

12. 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

13. 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

14. 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

15. Scoring Presentation • Tables A-1 and A-2

16. Normative Data • See table 4.1

17. Reliability and Validity • See back of test

18. GARS II and ABA • See Chapter 7 in Examiner Book and Instructional Objectives for Children Who Have Autism

19. 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

20. 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)

21. Recommended Usages • Recommended not as primary measure • Autism specialists • Interpret with skepticism

22. Questions

23. 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.

24. 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.