Functional Behavioral Assessment

Functional behavioral assesssment is an interactive model that connects a patient's problematic behavior with their cognitions and emotions. It takes into account both the triggers and the consequences of their behavior.
Functional Behavioral Assessment

Last update: 17 August, 2021

Functional behavioral assessment (FBA) is a process that seeks to find out the function of certain problematical behaviors. It looks for the purpose of the behavior as opposed to the cause. All behavior has a certain function. In fact, whenever you do something, you’re doing it for a reason. Furthermore, there can be different behaviors with the same function.

For example, say a child wants to get the attention of their mother. To do this they might have a tantrum or get angry with a sibling or say they’re sick when they’re at school so they have to be taken home. They could even have episodes of enuresis (bedwetting) and selective mutism. From an FBA perspective, these are all different behaviors that are carried out for the same purpose. In this case, to attract the attention of the mother.

To work out what function a specific behavior is performing, a therapist needs to understand the background and the consequences that occur when the patient carries out the problem behavior. This is so they can reinforce another complementary behavior or new adaptive behavior. The challenge for the therapist is to observe the patient’s overall behavior and deduce its function.

A girl looking worried.

The basis of functional behavioral assessment

FBA is an interactive model that connects problematic behavior with the patient’s cognitions and emotions in a given situation. It connects them with the background of the behavior on one hand, and the consequences of the behavior on the other.

There’s always an interaction between emotions, behaviors, and cognition. FBA aims to understand the individual as a whole. Thought, images, and emotions all form a part of the individual’s behavior.

Functional behavioral assessment is a process used to define and understand a person’s unique functioning. In fact, the therapist personalizes the therapy.

For this reason, the therapist must identify the explanatory variables (independent and moderating variables) involved in the problematic behavior of an individual (dependent variables). This must be in the context of both their current and past life.

Intervention in functional behavioral assessment

FBA seeks to replace the behavior identified as a problem with another more appropriate behavior. It isn’t a limiting method that intends to place restrictions on the individual. Instead, it tries to understand the logic behind their behavior.

The method of functional behavioral assessment

FBA is different from the categorical approach where each disorder is considered and diagnosed separately. In fact, FBA treats the patient as a whole. It also places great emphasis on the environment in which the behavior occurs. It prioritizes the following aspects:

  • The therapist identifies the patient’s complaints.
  • The therapist collects data. This might be by direct observation or from the patient themselves. It allows them to establish a baseline measurement. They take into account both the present knowledge as well as what they assume to be the origin of the behavior, and how it’s been maintained over time.
  • From these hypotheses, the therapist works out what techniques to use. They discuss these techniques with the patient in order to choose an appropriate method. If they find the chosen technique has no impact, they change to another.

During this stage, the therapist and patient explore the problem together in its diachronic dimension (history of the problem) and its synchronous dimension (the here and now)

The history of the problem behavior

With FBA, it’s crucial for the therapist to know the history of both the patient and their problem behavior. They ask questions about the patient’s past, as far back as childhood if necessary, to try and understand how the disorder first appeared. What they’re looking for are any biological or genetic origins of the disorder. Furthermore, family, social, and cultural elements can all play a part.

For example, the agoraphobic patient will always remember clearly when they first panicked outside the home. However, other disorders like depression and generalized anxiety disorder (GAD) might be more insidious.

Sometimes, disorders don’t appear at any prescribed time in life. In fact, they might appear when the patient’s coping resources are low, or when they’re stressed, exhausted, or have suffered some form of trauma.

The patient’s history

With FBA, the therapist tries to see how the person functioned before. Furthermore, they try and find out more about them. For example, are they pessimistic, optimistic, anxious, carefree, etc? What schooling and career path have they followed?  In this way, the therapist tries to build an image of the patient.

They also need to know if there could be a medical element to their condition. For example, are they genetically predisposed to any particular condition? Also, how has the family coped with any such disorders in the past? These kinds of factors can mean a patient is more vulnerable thus predispose them to certain behaviors.

Analyzing the patient’s current condition

The patient is seeking help in the here and now. For this reason, the analysis is basically quantitative. The therapist may give them questionnaires to fill in. They also might ask them to keep a diary for the purposes of self-observation.

The therapist needs to work out when the disorder started. This means they’re able to be more objective in the treatment they choose. In most cases, for each problematic behavior, they’ll want to know its:

  • Frequency.
  • Intensity.
  • Duration.
  • The different ways in which it manifests itself.

These measures and information are useful in different ways. They help the therapist to understand the dynamics of the problem and the vicious cycles that are sustaining them. They also help them to evaluate the patient’s subjective experiences with quantitative measures.

A woman making notes.

What does FBA assess?

FBA assesses problematic behaviors. However, it also assesses non-problematic behaviors. In fact, non-problematic behaviors are designated as resources for the patient.

Occasionally, situations that appear to be extremely similar might lead to problematic behavior in some instances yet not in others. For example, say a person starts protesting loudly when they’re assigned a particular task at work. We might think they’re objecting because they don’t want to work with others. Hence, we feel that they shouldn’t be given group tasks. However, we might not have taken into account all the times they previously did actually work in a group. Furthermore, they did it well. Consequently, we should consider that perhaps the problematic element on this occasion is elsewhere. For instance, a noisy environment, lack of appropriate colleagues to work with, tiredness, etc.


The psychotherapeutic treatment proposed in behavioral therapy is derived from FBA.

Furthermore, FBA has intense therapeutic properties. This is because it permits the patient to understand the mechanisms that trigger and maintain their problem behaviors.


This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.