Assessment validity is critical when it comes to evaluating individuals with certain developmental delays. Things like intellectual disability (ID), autism spectrum disorder (ASD), and attention-deficit/hyperactivity disorder (ADHD) are common ailments found in children, adolescents, and adults.
The need to evaluate, diagnose, and treat these individuals early and appropriately is reliant mainly on a standardized test by which these individuals can be examined. Determining an individual’s ability to function in and adapt to different daily environments is critical.
The reliability of the test leads to more effective communication and treatment of the individual. Stable results when evaluated by two parties, for instance, a parent and a teacher, can identify the areas in which the individual needs the most help and in which situations. Without a reliable test, this data cannot be confirmed.
The internal structure of the ABAS-3, or the Adaptive Behavior Assessment System, must provide a solid foundation on which to evaluate individuals and their behavior. The test’s internal structure is based on the relationships between how test items conform to the constructs on which the scores are based and how consistent the results are across different age groups.
By defining adaptive skill areas, domains of conceptual, social, and practical adaptive functioning, and overall adaptive behavior, the internal structure of the ABAS-3 can be established. While each test item should remain internally consistent and sensitive to different age ranges, they should also share a common variance, but be independent of one another.
The relationships of scores derived from items on the ABAS-3 should demonstrate consistency for the purposes of test accuracy. Acceptable levels of internal consistency have proved the reliability and stability of the ABAS-3.
Even slight deviations due to human error have not had an impact on the consistency of the scores of individuals when evaluated by two separate mediators or on two different forms.
Age Group Differences
Although adaptive skills and developmental milestones vary among different age groups, the ABAS-3 is designed to show consistency in results across these demographics. There are adaptive skills that children acquire early, like tying shoes, and there are adaptive skills that are learned later, like paying bills.
A lot of adaptive skills plateau in development before adulthood, meaning adults don’t display significant increases in these skills as they get older. In children and adolescents, however, these items can be translated to different age groups.
Because the ABAS-3 items are sensitive to age differences, the ABAS-3 remains internally consistent while allowing for each adaptive skills area to demonstrate appropriate levels of variance and independence.
The effectiveness of the ABAS-3 in different age groups and across varying adaptive skills disorders such as ID, ASD, and ADHD shows that the exam is reliable and resistant to standard errors of measurement. Teachers, caregivers, physicians, and parents can use the ABAS-3 to gain better insight into their child’s adaptive skills behaviors and establish a treatment plan accordingly.
WPS offers additional materials for understanding and using the ABAS-3 to evaluate your child. Check out more information on the Adaptive Behavior Assessment System, Third Edition, and other products at WPS Publish online.