Antecedent-Behavior-Consequence (ABC) Chart              

How is the Antecedent-Behavior-Consequence (ABC) Chart used? 

An ABC Chart is a direct observation tool that can be used to collect information about the events that are occurring within a student's environment. "A" refers to the antecedent, or the event or activity that immediately precedes a problem behavior. The "B" refers to observed behavior, and "C" refers to the consequence, or the event that immediately follows a response.

For example, a student who is drawing pictures instead of working on his class assignment may react by cursing or throwing his pencil when his teacher tells him to finish the task. The teacher may discover verbal requests to work and other demands are antecedents that trigger problem behavior. Common antecedents include critical feedback from others, absence of attention, and specific tasks or activities. The consequence may be that the teacher sends the student to the office every time he curses and throws his pencil. Over several observation sessions, it may become clear that the student is engaging in problem behavior to escape from his class assignment.

An ABC Chart is used to organize information over several observation sessions by recording the types of behaviors observed and the events that precede and follow the behavior. Observing and recording ABC data assists the team in forming a hypothesis statement and gathering evidence that the function maintaining a problem behavior has been identified.

Click here for an example of a completed ABC Chart.

Click here for a blank ABC Chart.

An ABC Chart can also be used to identify antecedent events that are associated with the nonoccurrence of problem behavior. Some intervention strategies involve modifying a student's environment by introducing antecedents and consequences that are associated with desirable behavior in other situations. For instance, a student may raise his hand and participate in class discussions when his teacher frequently reminds students to raise their hands and provides high levels of positive attention throughout the class (antecedent events). This teacher provides positive feedback for hand raising and participation (consequence).

However, in another setting, the teacher does not respond to the student when he raises his hand and provides low levels of positive attention to the student throughout the class period (antecedent events). In this class, the student does not raise his hand, yells his teacher's name out loud when he needs assistance, and wanders out of his seat, all of which attract the teacher's attention. He or she then reprimands the student for misbehaving (consequence). Understanding the antecedent events that are associated with both the occurrence and nonoccurrence of problem behavior can help you modify the characteristics of a difficult situation. The antecedent events that trigger positive behaviors can be introduced into another setting associated with disruptive behavior.

What role does the ABC Chart play in a functional assessment? 

The ABC Chart is a direct observation tool that provides information about what is really happening in the student's environment. The information gathered in the functional assessment interviews are compared to information from observations occurring in the environment. Confidence in a hypothesis statement increases when evidence for the function maintaining a behavior shows up across a number of functional assessment tools. Direct observation is especially important since it is less subjective than interview strategies that rely on memory and a person's perceptions.

What are the advantages and disadvantages of the ABC Chart? 

The ABC Chart allows an observer to record descriptive information about a student in a systematic and organized way. This recording format is easier to use than other observation forms that collect both scatter plot and ABC data such as the Functional Assessment Observation Tool included in this module. The data gathered provides a lot of descriptive information about the student's behavior and the environment.

A major disadvantage for using the ABC Chart is that it can be more difficult to see patterns quickly, and the data may need to be summarized to look for patterns related to antecedents and consequences. If a student engages in multiple problem behaviors, if there are several antecedents events, or if the student's behavior is being maintained by multiple functions, the ABC Chart may take more time to summarize compared to the Functional Assessment Observation Tool.

ABC Chart data is only correlational which means the causal relation cannot be confirmed. Strategies that systematically manipulate environmental antecedents and consequences, referred to as a functional analysis, are often used in research. However, in many cases, direct observations that include information about behavior, environmental events preceding and following the behavior, and time of occurrence are sufficient to provide confidence in the team's hypothesis statement.

When should the ABC Chart be used? 

The ABC Chart is often completed after initial interviews and record reviews are conducted, but these activities may occur concurrently. Functional assessment interviews can provide information about when and where observation sessions will be conducted.

How do you know when you have collected enough observational data? 

Each functional assessment is different, just as each student is unique and engages in different types of behavior. Direct observational data should be collected until the team members are confident about the function or functions maintaining a student's behavior. In simple situations, this may occur within 3-5 sessions. In more complicated cases, direct observation data may be needed across a number of settings and for longer periods. If your team remains unsure that the hypothesis statement(s) are accurate, find a professional with a background in applied behavior analysis or positive behavior support who can assist with the functional assessment. This professional may recommend different data collection methods or could assist in conducting a functional analysis.

Where can I find out more about the ABC Chart? 

Alberto, P. C., & Troutman, A. C. (1999). Applied behavior analysis for 
teachers (5th ed.). Columbus, OH: Merrill.
Bijou, S., Peterson, R. F., & Ault, M. H. (1968). A method to integrate 
description and experimental field studies at the level of data and empirical 
concepts. Journal of Applied Behavior Analysis, 1, 175-191.
Maag, J. W. (1995). Behavior management: Theoretical implications and 
practical applications. Lincoln, NE.
O'Neill, R. E., Horner, R. H., Albin, R. W., Sprague, J. R., Storey, K., & 
Newton, J. S. (1997). Functional assessment and program development for 
problem behavior: A practical handbook (2nd ed.). Pacific Grove, CA: 

Additional References

Bambara, L. M., & Knoster, T. (1998). Designing positive behavior support 
plans. Washington DC: American Association on Mental Retardation: 
Research to Practice Series. 
Rehabilitation Research and Training Center Product (1999). Facilitator's 
guide on positive behavior support. The Positive Behavioral Support 
Project, Department of Child and Family Studies of the Louis de la Parte 
Institute of the University of South Florida. 

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