Functional Behaviour Assessments

What is a Functional Behaviour Assessment?

A Functional Behaviour Assessment is a specific behavioural assessment designed to collect data on, obtain information about, and analyse the purpose a specific behaviour holds for a specific person. FBA’s are a process by which behaviour is analysed and effective treatment interventions are designed and implemented. It allows for a precise, effective and dignified treatment development.

To give you a matter-of-fact example of how this works, let’s use a familiar situation:
A newborn baby begins to cry. The mother picks up the baby but the baby continues to cry. The mother then checks the baby’s nappy, yet the baby continues to cry. Finally, the mother feeds the baby. The baby stops crying.

Why did the baby stop crying? What was the reason for the baby crying? Did the baby want attention? “No.” Did the baby want to get out of a dirty nappy? No. Did the baby want access to food? “Yes.” What we have just done is determined the function of the baby’s behaviour. We have uncovered the reason for the baby’s crying.

While in this scenario, the function of the behaviour was pretty straightforward, that is, the baby wanted access to food, human behaviour is seldom as such. A more accurate description of human behaviour is perhaps that of an exasperated mother and father saying something along the lines of “I have fed you, changed your nappy, played with you, and you have had your nap. Why are you still crying?” It is at this stage that Behaviour Analysts will employ scientific procedures and assessments to determine the function of a given behaviour. This type of assessment is called a Functional Behaviour Assessment, or FBA.

Why conduct a Functional Behaviour Assessment?
Every behaviour has a function, and each function falls under one of 4 categories:
1. access to an item or activity;
2. access to attention;
3. avoid or escape an item or activity; and
4. automatic reinforcement (i.e. sensory stimulation).

Often two or more behaviours may look the same but have a different function; i.e. the baby cries to communicate hunger, a baby also cries to communicate they need a nappy change, and may cry when they want to be held. However sometimes, two different behaviours may have the same function, i.e. a baby may cry when they want to be held, but the baby may also smile, coo and babble.

So how do we distinguish between the cries? How do we determine the function of the crying behaviour in a specific scenario? We do so via the FBA. Behaviour Analysts have long used FBA’s to analyse behaviour. Aside from being a treatment necessity, FBA’s are ethically mandated. Just as a doctor would run various tests in order to measure ones’ blood pressure and/or heart rate, so would a Behaviour Analyst conduct a FBA.

What is the process of a FBA?

The first step in an FBA is the collection of data. This is done in two forms: descriptive and indirect measures of the behaviour under investigation.

Descriptive measures of the behaviour take the form of direct observations of the individual across several settings and environments. The Behaviour Analyst records the ABC’s of the behaviour: the Antecedents (i.e. instructions or triggers that caused the behaviour), the Behaviours itself, including how long it lasted, how frequently it occurred, how long after the antecedent it occurred, and the magnitude of the behaviour), and the Consequences (i.e. what the other person or the other people do when the behaviour occurred).

It is important to observe the individual in different settings and environments, such as home, classroom, school playground, therapy session, at the park, etc. as a number of environment variables must be compared and evaluated. For instance, the behaviour might be occurring at high frequency at school because a child is given a lot of opened –ended free time, meaning he has trouble coping with the lack of structure. Whilst at home, their time is filled with a large variety of activities that have a beginning and an end, which eliminates anxiety.

This important information assists to evaluate the difference within the environments and the child’s response and behaviour in each. Furthermore, best results are obtained when the individual can be observed more than once in any environment. When aware that one is under observation, humans have the tendency to modify their behaviour. As such one observation at home may not give an accurate portrayal of the rate, frequency, or magnitude of a behaviour. Behaviours may occur more frequently, or not occur at all.

This is known as reactivity and refers to “the effects an observation or measurement procedure has, on the behaviour being measured.” Reactivity is most often observed when the individual knows they are being observed or their behaviours are being measured. Hence to ensure accurate data, it is recommended that more than one observation session takes place.

Indirect measures of behaviour take the form of interviews and questionnaires with parents, caregivers, teachers, day-care staff and other relevant personnel in the individuals’ life. It is important that individuals from different environments, such a school and home, are interviewed. The behaviour may be occurring more frequently in the presence of one person over another, in one environment compared to another, and often these individuals have a history of anecdotal evidence regarding the specific behaviour or other simular behaviours, that provide the Behaviour Analyst with additional information and data. Therefore data collection is a vital component of the FBA.

Once the individual has been observed in different environments, and all relevant personnel have been interviewed and the questionnaires have been administered, the real job of the Behaviour Analyst begins. The Behaviour Analyst will review, score, and analyse the data and develop a Behaviour Intervention Plan (BIP).
The final component of the FBA is the implementation of the BIP. We implement the intervention at home, at school, in day care/ afterschool care, in the playground, at grandma’s house and so-on. We provide weekly training for parents, grandparents, teachers, and others important individuals in your child’s life, and help you manage, and overcome your child’s problematic behaviours. We are guided by your child’s data and the scientific research, and make modifications and adjustments to your child’s BIP as necessary.

It is through this thorough understanding of the complexities governing human behaviour, and our reliance of the extensive scientific literature that AES is able to develop and implement effective treatment programs.

If you would like more information about FBA or are interested in having an FBA conducted with your child, please register your expression of interest by contacting us on 9240 5800 or by email at

Functional Behaviour Assessments