The B in the ABCs of Applied Behavior Analysis stands for behavior. This behavior can be any behavior we are interested in learning more about. When working with children it’s especially important to clearly define the behavior you are targeting. You can do this with 3 steps:
- Determine whether you need a topographic or functional definition.
- Describe the behavior.
- Follow your description with examples and non-examples to provide clarity.
Accurately and clearly defining the behavior is a key component of a functional behavior assessment. Although we frequently consider behaviors we want to reduce, we can also look at behaviors for increase in much the same way.
Key Takeaways
- Operational definitions are essential in ABA because they allow us to measure behavior objectively and reliably.
- There are two types of operational definitions: topographic and functional.
- Topographic definitions describe the observable features of a behavior.
- Functional definitions describe the purpose or function of a behavior.
- Clear and concise operational definitions are essential for effective communication and collaboration among professionals.
- Operational definitions can be used to develop effective interventions and to track progress over time.
Content
Define the Behavior
Topographic Definitions
Functional Definitions
Examples: 3 Key Components
Example: Aggression
Example: Self-Injurious Behavior
Example: Noncompliance
Example: Flopping
Example: Eloping
Example: Tantrum
Example: Crying/Screaming
Example: Swearing
Example: Throwing
Example: Climbing
Example: Grabbing
References
Related Posts
Define the Behavior
In order to really understand behavior, we must first define it. In Applied Behavior Analysis (ABA) we use operational definitions to define behavior. An operational definition describes behavior so that it is observable and measurable. It is written so that anyone who reads the definition will easily be able to identify if the behavior is occurring or not. It’s clear and offers both examples and non examples.
When creating an operational definition, a professional will avoid using language that places judgments or makes assumptions. Avoid language that discusses what the child feels when engaged in the behavior. Describe only what is visible to an observer.
Defining behavior to this level reduces confusion and ensures accurate data collection. This is especially critical if more than one person will be collecting data on the behavior.
Topographic Definitions
Topographic definitions describe how a behavior looks. These types of definitions identify a behavior by including observable actions.
- Running can be defined as: The rapid movement of one’s feet at a pace that exceeds normal walking speed.
- Aggression can be defined as: Any instance of forceful contact with sufficient force to leave a mark or make a sound audible.
The above definitions describe what the behavior looks like, but are they sufficient so that anyone reading the definition would know if the behavior occurred or not? Some questions remain:
- How far does the person need to travel for it to count as running?
- How far away does the person need to be standing to be able to hear the sound?
You can further clarify the definitions:
- Running: The rapid movement of one’s feet at a pace that exceeds normal walking speed for at least 5 steps.
- Aggression: Any instance of forceful contact with sufficient force to leave a mark or make a sound audible from 3 feet away.
These are better, but they continue to need clarification to ensure accuracy in data collection:
- Does it matter what direction the person is moving in?
- Does there need to be intent in the action?
The following definitions answer the above questions:
- Running: Rapidly moving in a forward trajectory through the movement of one’s feet at a pace that exceeds normal walking speed for at least 5 steps.
- Aggression: Any instance of intentional forceful contact with sufficient force to leave a mark or make a sound audible from 3 feet away. (*note-it may be argued that it is impossible to judge if the behavior was intentional or not)
Adding Examples
Finally, examples and non-examples delineate what counts as an occurrence of the behavior and what does not:
Running:
Rapidly moving in a forward trajectory through the movement of one’s feet at a pace that exceeds normal walking speed for at least 5 steps.
Examples include:
- Rapidly moving across the inside playground to access the swing before another child at a pace faster than normal walking speed.
- Rapidly moving down the hallway toward the exterior door at a pace faster than normal walking speeds.
Non-examples include:
- Rapidly moving out of the way of a moving vehicle in the parking lot.
- Rapidly moving 3 steps to sit at the table when directed to do so.
- Rapidly moving across the gym when running is part of the directed activity.
Aggression:
Any instance of intentional forceful contact with sufficient force to leave a mark or make a sound audible from 3 feet away.
Examples include:
- Hitting an adult’s bare arm with an open hand or closed fist with sufficient force to make a sound audible from a distance of 3 feet.
- Kicking a peer in the leg with sufficient force to leave a red mark on the skin of the peer.
- Biting another person with sufficient force to leave a mark on the skin.
Non-examples include:
- Making contact with a peer on the arm such that no mark was left and the sound was inaudible.
- Falling onto a peer resulting in a red mark on the peer’s skin.
The examples provide a picture for what the behavior looks like. The non-examples offer situations where it might appear the child engaged in the behavior, yet you don’t want to collect that data for some reason. In the case of aggression, you may be most interested in potentially dangerous behavior rather than the child making inappropriate contact with others. Therefore, you make the distinction regarding the level of force the child utilizes.
When to use a topographical definition
A topographical definition should be used when:
- You don’t have reliable information about the function of a particular behavior
- The behavior does not produce a consistent effect on the environment
- Other events produce similar effects on the environment
Functional Definitions
A functional definition defines the response class of behaviors by their common effect on the environment (the function). You use this form of operational definition to describe a group of behaviors that serve the same function. Here are a couple of examples.
Avoidance Behaviors:
Any instance in which the child responds to a demand by physically removing himself from the situation for greater than 20 seconds.
Examples include:
- Flopping to the ground and remaining there for longer than 20 seconds when told to line up for lunch.
- Eloping (moving more than 5 feet away from supervising staff) when told to sit at the table for work.
Non-examples include:
- Verbally protesting while engaging in the desired action.
- Flopping to the ground and standing up within 15 seconds of the demand to line up.
Stereotypic Behaviors:
Any instance in which the child engages in a behavior that results in a sensory experience through the physical movement of his body through space for more than 10 seconds.
Examples include:
- Flapping his hands when he hears “Row, Row, Row Your Boat.”
- Rocking back and forth and covering his ears when the volume in the lunch room reaches a level above conversational tones.
Non-examples include:
- Clapping his hands when imitating his peers during circle time.
- Rocking back and forth when dancing in gym class.
Functional definitions may require more examples and non-examples as they incorporate an entire class of behaviors. The examples provide the form (what the behavior looks like).
When to use a functional definition
A functional definition should be used when:
- The function encompasses all relevant forms of the response class
- The function of the behavior is what is most relevant
- You require a simple, concise definition
Key Points to Remember
- Do not use the word you are defining within your definition (i.e. defining darting as: darting in a forward or lateral motion)
- Ask someone else to read the definition and ask clarifying questions
- When errors in data collection occur, refine your definition
- Include as many examples and non-examples as is necessary to ensure clarity
- Anyone reading the definition should be able to tell instantly whether or not the behavior occurred
Writing operational definitions requires some practice. Remember these steps and keep refining the definition if it isn’t clear to everyone working with the child:
- Determine whether you need a topographic or functional definition.
- Describe the behavior.
- Follow your description with examples and non-examples to provide clarity.
Examples of Operational Definitions: 3 Key Components
Applied Behavior Analysis (ABA) requires careful collection and assessment of data to inform treatment decisions. Operational definitions allow for consistency in data as these definitions offer little confusion as to whether a behavior has occurred. Learning to write these types of definitions often feels daunting to professionals just entering the field.
Although they require some practice to write effectively, operational definitions are a key component in writing your behavior intervention plan (BIP) or when collecting data about specific behaviors. Operational definitions allow you to convey either what the behavior looks like (topography) or what function the behavior serves while providing sufficient detail to be clear. Take the time to practice and refine how you write your operational definitions!
Before you go on, learn the details about how to write operational definitions in our FREE course: Writing Operational Definitions. Each definition follows a set pattern and the course will provide this structure for you. In the course, there’s an opportunity to practice operationally defining behaviors (click the image below).
You can also download a PDF with some of these examples.
Operational Definition of Aggression
Aggression is commonly targeted for behavior reduction but can be difficult to define objectively as it’s really the effect on another person that we are concerned with and it often encompasses many different behaviors. Many children engage in multiple different types of aggressive behaviors including hitting, kicking, biting, and more. If your definition includes more than one of these behaviors, make sure each is also clearly defined.
When defining aggression, many try to make as broad a definition as possible to include attempts at aggression and mild aggressive behaviors. Instead, consider targeting the behaviors that present the most imminent risk of harm. As these behaviors reduce, you can then target “inappropriate physical contact” to address low risk behaviors.
Defining aggression may take more training of your interventionist than other definitions. Many people feel as though they already know what aggression is and use their own definition rather than relying on yours. Be clear with your interventionist about the threshold for aggression. If they want to include attempts or light hitting, assure them that you will target those behaviors once you have a sense of the scope of the truly dangerous behavior.
Here’s an example:
Aggression: Any instance of Richard making physical contact with another person using his body or an object with enough force to cause an audible sound and/or leave a visible mark on the skin.
Examples Include:
- Biting- teeth making contact with any part of the skin, constricting and leaving a mark
- Hitting- using a hand or arm with a closed or open fist to hit (making forceful physical contact) with another person
- Kicking – using the foot/feet or leg/legs to make contact with another person
- Throwing objects – any instance of him throwing items that are not designed to be thrown with enough force that the object makes physical contact with another person’s body making a sound on contact (not upon the object coming in contact with the floor) and/or leaving a mark on the person’s skin
Non-Examples Include:
- Giving a high five
- Hugging
- Common social physical interactions
- Saliva leaving his mouth as a result of talking or yelling
Operational Definitions for Self-injurious Behavior
Self-injurious behavior, also referred to as SIB, is similar to aggression in a lot of ways. The primary difference is the target. The child inflicts injury on himself or herself rather than another person. As with aggression, SIB may encompass many different topographies of behavior which may make it difficult to define.
When writing your definition, determine how specific or broad you want to be depending on staff skill, your plans for intervention or other factors. If you include multiple topographies of the behavior, consider including separate definitions for the topographies as in the aggression example above.
The following definition provides examples of each topography to ensure clarity:
Self-Injurious Behavior: Any instance in which Liam engages in any of the following: hitting self, pinching self, banging head on surface, slapping or biting self with sufficient force to make a sound and/or leave a mark.
Examples Include:
- Banging the front or back of his head on a hard surface.
- Hitting his head with his hands.
- Pinching his legs, arms or cheeks between his thumb and forefinger.
- Biting his hand, arm or leg by placing teeth on skin and compressing with sufficient force to leave a mark.
Non-Examples Include:
- Bumping his head on the ground when flopping to the floor.
- Banging his open hand on a table or hard surface.
Alternatively, you might choose to define just one topography of SIB if the child isn’t prone to multiple topographies or if you plan to treat different topographies separately.
Here’s an example:
Hand Biting: Any instance in which the teeth come into contact with any part of the hand with sufficient force to leave a mark.
Examples Include:
- Biting the hand between the thumb and forefinger with sufficient force to leave a red mark.
- Biting the hand below the thumb knuckle with sufficient force to leave teeth marks.
Non-Examples Include:
- Putting a finger in the mouth without leaving a mark.
- Putting the side of the hand in the mouth without leaving a mark.
Operational Definitions for Non-compliance
Non-compliance is another common behavior that is tricky to define. In ABA it actually isn’t considered a behavior because it doesn’t pass the Dead Man test. The Dead Man test states that if a dead man can do it, it’s not a behavior. Can a dead man fail to comply with a direction? Sure. Non-compliance is not a behavior.
That being said, in practice, you may be in situations where it’s reasonable to target this as a behavior for reduction. You may feel better about defining this as a behavior if you call it “Refusal” even if the child doesn’t actively protest when given a demand.
Here’s an example of a definition of this non-behavior:
Non-Compliance: Any instance in which Alex physically and/or verbally refuses to follow an instruction or complete a task.
Examples Include:
- Alex swiping materials off the table when presented with a task to complete.
- Alex refusing to complete a transition when directed to (may or may not flop on the floor).
- Alex not moving his body to initiate the task/follow the instruction within 30 seconds of the demand.
Non-Examples Include:
- Alex engaging in a response that matches the delivered instruction.
Onset: 30 seconds of occurrence
Offset: Initiation of compliance with directive
*Note that onset and offset have been included in this definition as it’s a “behavior” that doesn’t have a clear start and stop so would likely be recorded using duration recording.
An alternative to trying to define a behavior that’s not actually a behavior is to target the opposite of that behavior for increase. Here’s what I mean: target compliance with adult demands for increase.
Here’s what that might look like:
Compliance: Any instance in which Alex follows an instruction or completes a task as directed by an adult within 30 seconds.
Examples Include:
- Alex completing a transition within 30 seconds of an adult requesting he do so.
- Alex engaging in a behavior specified by an adult.
Non-Examples Include:
- Alex taking longer than 30 seconds to initiate a task after being given a direction from an adult.
- Alex starting a transition when directed to do so but flopping after taking only 5 steps.
Operational Definition of Flopping
Flopping looks different for many children and the definition should reflect what is common for your client. In addition, you should consider whether you want to include aspects that are less common for your client. For example, if your client typically falls flat on the floor on his back, do you exclude all other topographies? How should staff respond if he falls to his knees or stomach?
Make sure to purposefully include or exclude each topography based on your desire to either restrict or expand the definition. This should reflect your plan in how you want your interventionists to collect data and implement a Behavior Intervention Plan.
Take a look at this example:
Flopping: Any instance in which the Julian’s body goes limp resulting in his body in a kneeling or lying flat on the floor position.
Examples Include:
- Falling to his knees while walking in the hallway.
- Moving from standing to lying flat on the floor when given a directive by an adult.
Non-Examples Include:
- Lying on the floor in the motor room as part of a game he is playing.
- Kneeling on his mat at circle time.
Operational Definition of Eloping
Eloping is a behavior you might define as either a discrete event or as a duration. If the child elopes and frequently fails to return to the designated area, you may prefer to record how long the child remains away from where he should be. If an adult consistently follows the child to direct him back, then it may make sense to record the frequency or rate of the behavior.
Here’s an example:
Eloping: Any instance of Bowie moving away from adult more than 5 ft while outside or inside without permission.
Examples Include:
- Going across the room when directed to go to the table.
- Going down the hall toward the big clinic room when directed to go to the bathroom.
Non-Examples Include:
- Going across the room to get a toy from the shelf during choice time.
- Running in circles around the structure in the Motor Room during choice time.
Operational Definition of Tantrum
Tantrums are common of young children although they can be difficult to define because, like aggression and SIB, they include multiple behaviors in one. Any time you define a behavior that encompasses more than one behavior, consider the need to also define each of the behaviors separately.
Defining these behaviors can become cumbersome and confusing. If you record data for a behavior in a grouped behavior, that behavior should not be recorded individually as well. That can skew the data making it appear that the behavior occurs more frequently than it actually does.
Take a look at this definition:
Tantrum: Any instance in which Petra engages in 2 or more of the following behaviors at the same time: crying (vocalizations louder than normal speaking voice lasting longer than 3 seconds with tears), throwing (moving objects not intended to be thrown through space farther than 3 ft), banging floor (using any part of the body or an object to make contact with the floor with sufficient force to make a sound), screaming (vocalizations louder than normal speaking voice lasting longer than 3 seconds without tears), hitting (making forceful physical contact using one or both hands with another person with sufficient force to make a sound or leave a mark), and/or flopping (going limp resulting in the body in a kneeling or lying flat on the floor position).
Examples Include:
- Crying and flopping in response to a demand to transition.
- Screaming and throwing materials on the floor when given a task demand.
Non-Examples Include:
- Crying and laying on the floor in response to injuring herself.
- Stomping her feet and throwing a ball in the gross motor room as part of play.
Operational Definition of Crying/Screaming
Many children cry for a variety of different reasons and there may not be a need to intervene. However, some children may cry or combine crying with screaming to an excessive extent. When defining a behavior that is either developmentally or often contextually appropriate, consider including parameters that allow for those instances to be excluded from the definition.
Here’s an example, but you may need to exclude a wider range of contextually appropriate crying depending on your specific situation:
Crying/Screaming: Any instance in which Christopher engages in a vocalization louder than is used for communication for longer than 3 seconds during which time he may or may not produce tears.
Examples Include:
- Loud vocalizations accompanied with tears when presented with a task demand.
- Loud vocalizations not accompanied by tears when told he could not have the iPad.
Non-Examples Include:
- Laughing/giggling.
- Crying as a result of hurting himself.
Onset: 30 seconds of occurrence
Offset: 30 seconds of nonoccurrence
*Note that onset and offset have been included in this definition as it’s a behavior that doesn’t have a clear start and stop so would likely be recorded using duration recording.
Operational Definition of Swearing
It’s almost universally accepted that young children should not swear, but what words constitute a swear? When defining this behavior, you must be clear about which words are included or excluded from the definition. This may vary between different contexts, but that would be confusing to the interventionist. You should make the definition fit the strictest environment.
Over time, you may be able to target the behavior at different levels for different contexts depending on the child’s ability to discriminate between contexts. This would require clear guidelines for both the child and the interventionist.
Here’s an example:
Swearing: Any instance in which Jack uses language inappropriate to a particular environment.
Examples:
- Swearing (saying “sh..” or “fu..”) while in the clinic room or hallway.
- Swearing (saying “sh..” or “fu..”) while in a public location such as the library or Walmart.
Non-Examples:
- Saying words staff do not approve of that are not included in the specified list.
- Saying variations of the words included in the list (i.e. “shoot,” “fudge,” “darn,” etc.).
Operational Definition of Throwing
Throwing may seem straightforward, yet at what point does the behavior go from “pushing” or “displacing” an object to actually “throwing?” Make sure this is clear in your definition. Will sliding an object across a table be part of your definition? At what point does the behavior become problematic and meet your criteria for intervention?
Look at this example:
Throwing: Any instance in which Junior moves objects not intended to be thrown through space farther than one foot using any part of his body.
Examples Include:
- Pushing items off a shelf or table.
- Throwing a marker farther than one foot.
- Kicking a bucket resulting in the items in the bucket being dumped on the floor.
- Holding an inset puzzle upside down while standing resulting in the pieces being dumped on the floor.
Non-Examples Include:
- Turning an inset puzzle upside down over a table prior to completing the puzzle resulting in one or more pieces falling on the floor.
- Kicking or throwing a ball in the gross motor space.
Operational Definition of Climbing
Climbing is a behavior that is appropriate in many instances, but can be dangerous in others. For example, a child climbing on a jungle gym or ladder on the playground is behaving in a way we would want and encourage. On the other hand, a child climbing a bookcase and jumping off the top is at risk of injury. When defining a behavior like this, make sure that you’re including the context within which the behavior is problematic.
Look at this example
Climbing: Any instance in which Keith is inside, not in a prone or sitting position, and has both hands and both feet off the ground and onto another surface that is higher than 3 feet.
Examples Include:
- Hands and feet on the bookcase on a shelf higher than 3 feet.
- Keith standing on the counter in the kitchen.
- Keith standing on the back of the couch.
Non-Examples Include:
- Laying in bed.
- Sitting on the couch.
- Standing on a step-stool to reach the counter when helping to make cookies.
Operational Definition of Grabbing
Grabbing is another behavior that is appropriate in some contexts but not all. I want a child who is falling to grab onto me to stop herself from falling. I don’t want a child to grab onto the shirt of another child whenever they walk by. As with climbing, make sure to include details about the context that’s problematic in your definition.
Look at an example
Grabbing: Any instance in which Abby’s fingers curl into, around or through the clothing, hair or body part of another person without permission except to prevent a fall or to stop someone else from getting hurt.
Examples Include:
- Abby’s fingers becoming entwined in the shirt of a peer walking past her desk.
- Abby’s fingers curling around the hair of her teacher.
- Abby’s fingers curling around the hand of a peer on the playground as the peer runs past her.
Non-Examples Include:
- Abby’s fingers becoming entwined in the shirt of a peer as the peer starts to fall down the stairs.
- Abby’s fingers curling around the hair of her teacher after tripping over a book on the floor.
- Abby’s hand resting on a peer’s arm.
Operational Definitions of Behavior
Clear operational definitions ensure accurate data collection and implementation of interventions. As interventionists ask for clarification or make errors, hone your definitions to be clearer by including more examples and non-examples or by including more detail. Your definitions should leave no question about whether the behavior occurs or not in any given moment.
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References
Kubina Jr, R. M., Halkowski, M., Yurich, K. K., Ghorm, K., & Healy, N. M. (2022). Comparing the Detection Accuracy of Operational Definitions and Pinpoints. Journal of Behavioral Education, 1-21.
Peterson, L., Homer, A. L., & Wonderlich, S. A. (1982). The integrity of independent variables in behavior analysis. Journal of applied behavior analysis, 15(4), 477-492.
Ribes-Iñesta, E. (2003). What is defined in operational definitions? The case of operant psychology. Behavior and Philosophy, 111-126.