Adaptive Behaviour Assessment System - Second Edition (ABAS-II)

Full Name of Assessment:		ABAS –II  (Adaptive Behaviour Assessment System – Second Edition)
Author, Publisher, Date:		Patti Harrison and Thomas Oakland, Western Psychological Services, 2003
Source:		Pearson	Pricing: $231.00
Brief description (purpose, domains, subscales, time to administer, space/equipment needs): Purpose:  The ABAS-II can be used to assess an individual’s adaptive skills: To assist in the diagnosis and classification of disabilities and medical/clinical disorders For the identification of adaptive skill strengths and difficulties in a person’s daily living environment  For the identification of service needs in treatment or intervention programs  For research related to adaptive skill progression (i.e., intervention program evaluations) Age Range: birth to 89 years Domains: 10 skill areas:  communication, community use, functional academics, home living, leisure, self-care, self-direction, social, work (optional) Subscales: Each skills area is grouped into 3 adaptive domains:  Conceptual (communication + functional academics + self-direction), social (leisure + social), and practical (community use + home living + health and safety + self care).  The “work” skill area is considered to be a separate, optional domain.  Since several skill areas do not apply to certain age groups (i.e. work and home living skills are not relevant to a toddler), the GAC score is calculated based on only applicable scales. Time to Administer: each respondent form in the ABAS-II should take between 20-30 minutes to complete.  Scoring should take approximately 10 minutes per form. Space/Equipment Needs:  examination kit (each kit is targeted to a specific group and contains the following forms depending on kit:  Parent Form, Birth-5; Parent Form, 5-21; Teacher/Day Care Form, 2-5; Teacher Form, 5-21; Adult Form, 16-89)
Scoring: Each item can be answered “0” (is not able to perform the task), “1” (never or almost never performs the task), “2” (performs the task sometimes), or “3” (always or almost always performs the task); the respondent also indicates for each item whether her/his response was a guess or an estimate. Raw scores are calculated by tabulating totals for the items answered in each skill area.  The raw scores can be converted into composite scores, a skills profile, scaled scores, percentile ranks, domain-specific scores, descriptive classifications, and test-age equivalents.  A professional with formal coursework in education assessment must interpret the scores.  The skills ares are combined to created the “general adaptive composite” (GAC) score that represents a norm referenced score for the individual.
Psychometric properties (describe briefly; e.g. reliability, validity, sensitivity, specificity, etc): Reliability:  Internal consistency:  range from .97 to .99 for the GAC scores, .91 to .98 for the adaptive domains (i.e., conceptual, social), and .80 to .97 for the 10 individual skill areas.  Correlation coefficients were also high for individuals with clinical diagnoses and all age groups, indicating that the test shows a high degree of consistency for examinees with a wide range of adaptive functioning. Test-retest reliability:  reliability coefficients in the .90s (excellent) for GAC scores, .80s to .90s for adaptive scores, and .70s to .90s for skill areas. Inter-rater reliability:  varies across each of the forms used, but in general was good, between .82 and .91 for GAC, .78 and .84 for adaptive domains, and .70 to .82 for skill areas.  Cross-Form reliability:  correlations between teacher/daycare provider and parent/primary caregivers scores averaged between .68 and .70 for GAC, .62 and .70 for adaptive domain scores, and .51 and .66 for skill areas – all moderate to good reliabilities. Validity: Age group differences:  strong sensitivity to age group Construct and convergent validity:  across all forms the intercorrelations between skills areas were .40s to .70s, the averaged intercorrelations between skill areas and adaptive domains were .60s to .70s, and the intercorrelations between skill areas and the GAC were .60s to .80s  Factor structure:  factor analysis on the entire standardization sample data set, yielded s single-factor structure, meaning it assesses a single factor related to general adaptive skill Sensitivity and Specificity: Children with clinical diagnoses (e.g., developmental delays, motor impairments, receptive/expressive language deficits) typically showed performance at least 2 SDs below the mean of a control group. Adults with diagnoses (e.g., neuropsychological disorders, Alzheimer’s disease) typically performed at least 2 SDs below the mean compared to control groups. Demonstrates good sensitivity for clinical populations. Demonstrates good specificity
Citations/References (source at least 2 articles that use the tool or reports on psychometrics): Perkins-Dock, R. E. (2003). Test Review - Review of Adaptive Behavior Assessment System. Rehabilitation Counseling Bulletin, 46, 3, 183. Aricak, O. T., & Oakland, T. (December 01, 2010). Multigroup Confirmatory Factor Analysis for the Teacher Form, Ages 5 to 21, of the Adaptive Behavior Assessment System-II. Journal of Psychoeducational Assessment, 28, 6, 578-584.
Comments/critique (include application to practice – settings, needs, populations): Parent assessment form is free of jargon and easy to understand.  The rating form can be completed on-site (i.e., clinic, school, agency, etc.) or off-site (i.e., home).
Training or certification requirements:	B,Q1,Q2-Level (must be either: (a) trained and certified by a recognized institution in a relevant area of assessment (w/ or w/out Master’s degree), (b) a member of a SLP or OT association, or (c) possess a Master’s (or Doctorated) degree in psychology, education, or relevant field with training in assessment