Post your job application on ABA Therapist Jobs today!
Post job

Why Conduct FBAs?

Functional behaviour assessments are now a professional standard and are mandated by court decisions. Without identifying the functions of a behaviour an intervention may make the behaviour worse.

Why Conduct FBAs?

"Functional Assessment is now a professional standard for psychologists, teachers, and adult service providers delivering behavioural support to children and adults with disabilities" - O’Neill, Horner, Albin, Sprague, Storey, and Newton (1997, p. 6)

Functional Assessments Are a Professional Standard

Within both research and applied settings (e.g. Applied Behaviour Analysis), functional assessments are regarded as best practice and ‘have been mandated in recent court decisions and legislation on behalf of persons with developmental disabilities who have severe behaviour disorders.’ (Iwata et al, 2000, p. 181).

Interventions Based On FBAs Are Typically More Effective

By identifying why a problem behaviour is occurring, practitioners can then develop an intervention that will directly address the function of the behaviour. As a result, interventions based on functional assessments are typically much more effective than interventions that are not (Cooper, Heron, & Heward, 2007).

For example, a meta-analysis was carried out by Kokina and Kern (2010) in an effort to investigate the effectiveness of social story interventions for children with Autism Spectrum Disorders. Their analysis found the stores that were implemented using the information gathered from a functional assessment were substantially more successful than those that did not.

Challenging Behaviours Can Be Accidentally Made Worse

Without fully understanding the reason a person is engaging in a challenging behaviour there is a real danger of inadvertently reinforcing the behaviour to the extent that practitioners, teachers or parents are actually maintaining the behaviour or even making it worse (O’Neill et al, 1997).

Consider this hypothetical example: a boy with limited communication skills (e.g. single words) has started to kick his teacher under the desk at school. The school have no clear understanding of why he has started to do this and as he cannot communicate fully to give a reason they are completely in the dark.

Up until now the school policy has been that behaviour like this leads to the student being removed to a table in the corner of the class where he has to sit for a period of time before being allowed to come back to his desk (non-exclusionary time-out). However, the school are noticing that even though he is being “punished” for kicking his teacher, this behaviour is continuing and so they decide to have a functional assessment carried out in order to understand why.

The assessment identifies that just before the self-injury occurs the student is at his desk and is being instructed to complete mathematics tasks in a one-to-one setting. It also identifies that just after kicking his teacher he is guided to the time-out table where he has to sit for a period of time before going back to his desk.

It is also noted that he never kicks his teacher when he is completing any academic task other than mathematics and that he never engages in this behaviour at any other time throughout the school day.

Please note that the assessment would look at numerous other things that are happening within the school environment but for the sake of brevity we’re not going into too much detail on it all.

From the information gathered through the assessment, it becomes clear to the school that the reason this boy is kicking his teacher is because he gets away from having to complete mathematics tasks.

Although putting this boy into time-out seemed like a punishment, it was instead giving him exactly what he wanted (i.e. to get away from math tasks) and so the school were inadvertently rewarding him for kicking his teacher.

In this case you would say the function of the kicking behaviour was to escape from math tasks (a form of negative reinforcement). By having this crucial piece of information, the teachers and practitioners would then be able to intervene and put a programme in place that would directly address this behavioural function and reduce the challenging behaviour.


  • Cooper, J., Heron, T., & Heward, W. (2007). Applied Behaviour Analysis. New Jersey: Pearson Education.
  • Iwata, B., Wallace, M., Kahng, S., Lindberg, J., Roscoe, E., Conners, J., Hanley, G., Thompson, R., & Worsdell, A. (2000). Skill Acquisition in the Implementation of Functional Analysis Methodology. Journal of Applied Behaviour Analysis, 33, 181-194. DOI:10.1901/jaba.2000.33-181
  • Kokina, A., & Kern, L. (2010). Social Story Interventions for Students with Autism Spectrum Disorders: A Meta-Analysis. Journal of Autism and Developmental Disorders, 40, 812-826. DOI: 10.1007/s10803-009-0931-0
  • Miltenberger, R. (2008). Behaviour Modification. Belmont, CA. Wadsworth Publishing.
  • O'Neill, R., Horner, R., Albin, R., Sprague, J., Storey, K., & Newton, J. (1997). Functional Assessment and Programme Development for Problem Behaviour: A Practical Handbook. Pacific Grove, CA. Brooks/Cole Publishing Company.

Learn More

The best new BCBA and RBT jobs straight to your inbox