The Adaptive Behavior Assessment System (ABAS)

The Adaptive Behavior Assessment System (ABAS), developed by Patti Harrison & Thomas Oakland, is a method for comprehensive measure individuals with an adaptive behavior scale. ABAS is specifically used for responses to daily demands, formulating treatment steps, eligibility for service and Social Security, assessing a list of impairments and the individuals ability to independently live.

The format for the test consists of several different forms: Parent Form (232 items), Teacher Form (193 items), and the Adult Form (239 items). A 4-point rating scale ranging from 0 = not able to 3 = always for responses. Completion time for respondents is approximately 15-20 minutes and should only be administered to individuals ranging between 0 and 89 years.

Authors: Patti Harrison & Thomas Oakland, 2000

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Reliability and Validity

Internal Consistency is extremely high for the GAC, adaptive domains, and each skill area. Reported test-retest coefficients for all subscales in the teacher form are above 0.90, along with its GAC (General Adaptive Composite). The Parent Form shows lower rating with its test-retest coefficient as 0.79 and a GAC of 0.96. The inter-rater reliability coefficient differentiated greatly between these two forms. Studies exploring correlations with the ABAS instrument are shown with the Vineland-Classroom Edition (0.75-0.84), Independent Behavior Revised, WISC-III, WAIS-III, WASI, Stanford Binet Fourth Edition, and the WIAT. A correlation rating of 0.82 was calculated with the Vineland composite and the Teacher Form GAC. Moderate rating were presented between the ABAS form and intelligence measures. Each form of the ABAS has shown strong sensitivity to a particular age and is suggested that participants remain in the recommended age range.

Where to Purchase

Instrument at Pearson

Adaptive Behavior Assessment System-II: Clinical Use and Interpretation (Practical Resources for the Mental Health Professional)

Administration, Analysis and Reporting

Statistics Solutions consists of a team of professional methodologists and statisticians that can assist the student or professional researcher in administering the survey instrument, collecting the data, conducting the analyses and explaining the results.

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American Association on Mental Retardation. (2002). Mental retardation: Definition, classification, and systems of support (10th ed.). Washington, DC: Author.

American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: Author. View

Grossman, H. J. (Ed). (1983). Classification in mental retardation. Washington, DC: American Association on Mental Deficiency.

Harrison, P. L., & Oakland, T. (2000). Adaptive Behavior Assessment System. San Antonio, TX: The Psychological Corporation. View

Harrison, P. L., & Oakland, T. (2003). Adaptive Behavior Assessment System–Second Edition. San Antonio, TX: The Psychological Corporation.

Heber, R. (1959). Modifications in the manual on terminology and classification in mental retardation (monograph suppl.). American Journal of Mental Deficiency, 64(2), 499– 500.

Individuals with Disabilities Act Amendments of 1997, 20 U.S.C. 1431 et seq (Fed. Reg. 34, 1997).

Dissertations and Journals

Wei, Youhua, Oakland, Thomas, Algina, James (2008). Multigroup Confirmatory Factor Analysis for the Adaptive Behavior Assessment Form. American Journal on Mental Retardation, v113, n3, 178-186.

Kay B. Stevens & J. Randall Price (2006). Adaptive Behavior, Mental Retardation, and the Death Penalty. Journal of Forensic Psychology Practice, Vol. 6, Issue 3, 1-29.

James R. Patton & Denis W. Keyes (2006). Death Penalty Issues Following Atkins. Exceptionality: A Special Education Journal, Vol.14, Issue 4, 237-255.