top of page

Functional Assessment Methods in ABA

A functional assessment is a required precursor to any behavior intervention plan. It helps us identify problem behaviors, hypothesize their function, and guides our treatment development. There are 3 primary methods for determining function which should be used together, not one or the other.

Check out this freebie to easily track A-B-C data during assessments and in therapy!

Free, no-strings attached, login required to access all of the freebies at ABC Behavior Training

Indirect Assessment

This type of assessment is typically conducted with parents, caregivers, teachers, and anyone else in the client's environment. It can even include the client if they are able to participate, but it indirectly gathers information about the behaviors of interest without directly observing them. Some indirect assessments include structured or open-ended parent interviews as well as rating scales such as the Questions About Behavior Function (QABF) or the Motivation Assessment Scale (MAS).


  • Quick and easy to use

  • Low risk as behaviors don't have to occur

  • Useful for low-frequency or difficult to assess behaviors


  • Not reliable

  • Unclear method for determining function

  • Requires faithful recollection of behaviors

Descriptive Assessments

This type of assessment is conducted in the natural environment where the behavior is occurring and can be observed directly. Direct assessments can include narratives, A-B-C data, scatterplot data, and more.


  • You can see the full range of antecedents and consequences

  • Any environmental variables affecting the behavior can be observed


  • The data is correlational

  • May have reactivity from the client

  • Could be difficult to obtain an adequate sample of the behavior

Functional Analysis

This type of assessment contrives conditions to simulate circumstances that evoke the problem behaviors. Behaviors in the test and control conditions are compared to determine the function of the behavior.


  • It determines the ACTUAL function of the behaviors, not correlational

  • May reveal potential treatment effects


  • Complex and time-intensive

  • Might not include relevant test conditions

Be sure to check out the ABC Behavior Training Membership Access for tools and resources for assessments, programming, supervision, and more!


Recent Posts
bottom of page