Differential Reinforcement (DRI) in ABA Therapy

Unlock the power of differential reinforcement in ABA therapy! Discover how DRI can transform behavior and promote positive outcomes.

November 21, 2024

Understanding Differential Reinforcement

Differential reinforcement is a behavior modification technique used in Applied Behavior Analysis (ABA) that involves selectively reinforcing desired behaviors while withholding reinforcement for undesired behaviors. This approach aims to increase the occurrence of desired behaviors and decrease or eliminate problem behaviors. By using differential reinforcement, individuals can learn new, more adaptive behaviors [1].

Basics of Differential Reinforcement

Differential reinforcement involves the systematic application of positive reinforcement and negative reinforcement. Positive reinforcement refers to providing a pleasant stimulus after a behavior, which increases the likelihood of that behavior occurring again in the future. Negative reinforcement, on the other hand, involves removing an unpleasant stimulus after a behavior, also increasing the likelihood of that behavior being repeated.

The use of positive reinforcement and negative reinforcement is based on the principle that behaviors that are followed by a positive outcome or the removal of an aversive stimulus are more likely to recur in the future. By selectively reinforcing desired behaviors and not reinforcing undesired behaviors, individuals can learn to replace problem behaviors with more appropriate alternatives.

Types of Differential Reinforcement

There are several types of differential reinforcement techniques used in ABA therapy. These techniques focus on reinforcing specific behaviors to shape behavior change. Some common types of differential reinforcement include:

Each type of differential reinforcement has its own unique application and can be used based on the specific needs and goals of the individual undergoing ABA therapy.

Understanding the basics and types of differential reinforcement is essential to grasp the application and effectiveness of this behavior modification technique. In the subsequent sections, we will explore how differential reinforcement techniques, such as DRI, are utilized in ABA therapy and its role in autism intervention.

Differential Reinforcement Techniques

When it comes to differential reinforcement, there are various techniques used in Applied Behavior Analysis (ABA) therapy. These techniques aim to promote positive behavior change by utilizing different types of reinforcement. The key differential reinforcement techniques include positive reinforcement, negative reinforcement, differential reinforcement of alternative behavior (DRA), differential reinforcement of incompatible behavior (DRI), and differential reinforcement of other behavior (DRO).

Positive Reinforcement

Positive reinforcement involves providing a pleasant stimulus or reward following a desired behavior. This technique aims to increase the likelihood of the behavior occurring again in the future. By associating the behavior with a positive outcome, individuals are motivated to continue engaging in the desired behavior. Positive reinforcement can be implemented through the use of praise, tokens, tangible rewards, or access to preferred activities. To learn more about positive reinforcement in ABA therapy, refer to our article on positive reinforcement in ABA therapy.

Negative Reinforcement

Similar to positive reinforcement, negative reinforcement is a technique used to increase the occurrence of a desired behavior. However, it involves removing an unpleasant or aversive stimulus after the behavior occurs. This removal of the aversive stimulus serves as a reward, reinforcing the behavior. Negative reinforcement can be effective in motivating individuals to engage in the desired behavior to avoid or escape the aversive stimulus.

Differential Reinforcement of Alternative Behavior (DRA)

Differential reinforcement of alternative behavior (DRA) is a technique used to increase the occurrence of a desirable behavior while decreasing or eliminating an undesirable behavior. This involves reinforcing a behavior that serves as a suitable alternative to the problem behavior. For example, if a child engages in disruptive behaviors to gain attention, the DRA technique would involve reinforcing appropriate behaviors that achieve the same goal of gaining attention. By providing positive reinforcement for the alternative behavior, the individual is motivated to engage in the desired behavior instead of the problem behavior. Research has shown that DRA can be effective in promoting behavior change in typically developing children [2].

Differential Reinforcement of Incompatible Behavior (DRI)

Differential reinforcement of incompatible behavior (DRI) is a technique that focuses on reinforcing behaviors that are incompatible with the problem behavior. In other words, the individual cannot engage in both behaviors simultaneously. By reinforcing the incompatible behavior, the occurrence of the problem behavior is effectively reduced. For example, if a child engages in hitting behaviors when feeling frustrated, the DRI technique would involve reinforcing a behavior like using words to express frustration, which cannot be done while hitting. Research has indicated that the effectiveness of DRI is influenced by the functional relationship between the incompatible behavior and the problem behavior [2].

Differential Reinforcement of Other Behavior (DRO)

Differential reinforcement of other behavior (DRO) involves reinforcing the absence or non-occurrence of a problem behavior for a specified period of time. It focuses on reinforcing periods of time when the problem behavior does not occur. DRO can be effective when the goal is to decrease the frequency or duration of a specific behavior. For example, if a child engages in self-injurious behaviors, the DRO technique would involve providing reinforcement for any period of time when the child does not engage in self-injury. This technique helps to shape behaviors by reinforcing the absence of the problem behavior. Research has shown that DRO can be a preferred alternative to other differential reinforcement techniques [2].

By utilizing these differential reinforcement techniques in ABA therapy, behavior analysts can help individuals with autism and other developmental disorders acquire and maintain positive behaviors while reducing problem behaviors. The selection of the most appropriate technique depends on the individual's specific needs and the goals of the intervention.

Application of Differential Reinforcement

Differential Reinforcement of Incompatible Behavior (DRI) is a valuable technique utilized in Applied Behavior Analysis (ABA) therapy, particularly in the context of autism intervention. By focusing on reinforcing behaviors that are incompatible with problem behaviors, DRI aims to reduce unwanted behaviors and promote the development of more appropriate alternatives.

DRI in ABA Therapy

In ABA therapy, DRI is employed as a behavior modification strategy to address problematic behaviors, especially in children diagnosed with autism. The approach involves identifying a behavior that is incompatible with the problem behavior and reinforcing it while withholding reinforcement for the problem behavior. By doing so, the likelihood of the problem behavior occurring diminishes, and the desired behavior becomes more prominent.

For example, if a child engages in aggressive behaviors such as hitting others, a suitable replacement behavior that is incompatible with hitting, such as using words to express frustration, would be identified and reinforced. The reinforcement may come in the form of praise, rewards, or other positive stimuli tailored to the individual's preferences and needs.

Implementing DRI in ABA therapy requires careful observation, data collection, and collaboration between therapists, parents, and other caregivers. Through consistent and systematic application, DRI can be an effective tool in shaping behavior and fostering positive changes.

DRI in Autism Intervention

DRI holds particular relevance in the field of autism intervention due to its focus on promoting adaptive behaviors and reducing maladaptive ones. By targeting behaviors that cannot coexist simultaneously, DRI offers individuals with autism an opportunity to develop and engage in alternative behaviors that are more socially appropriate and functional.

Research has shown that DRI, along with other differential reinforcement techniques, can be effective in improving various skills and reducing problem behaviors in individuals with autism. For instance, a study examining the impact of DRI on skill acquisition found that using DRI resulted in increased appropriate behaviors and decreased inappropriate behaviors [3]. Another study explored the effectiveness of DRI in young children and found that it led to a significant decrease in problem behaviors and an increase in appropriate replacement behaviors [4].

By incorporating DRI into autism intervention programs, therapists and caregivers can effectively target and address specific behaviors, paving the way for skill development, enhanced communication, and improved social interactions.

Differential reinforcement techniques, such as DRI, play a vital role in ABA therapy and autism intervention. By harnessing the power of reinforcement to shape behavior, individuals with autism can make significant progress in their overall development, leading to improved quality of life and increased independence.

Research Studies on Differential Reinforcement

To understand the effectiveness and impact of differential reinforcement (DRI) in skill acquisition and behavior modification, several research studies have been conducted. These studies shed light on the benefits and outcomes of using DRI techniques in various settings, including ABA therapy and interventions for young children.

Impact of DRI on Skill Acquisition

Karsten and Carr (2009) conducted a study comparing different DRI procedures and their impact on skill acquisition. The researchers found that differentially reinforcing unprompted responses may lead to more rapid skill acquisition. This suggests that when individuals are encouraged and reinforced for independently demonstrating the desired behavior, their ability to acquire new skills may improve.

Differential reinforcement of alternative behavior (DRA) is another technique commonly used in ABA therapy. Legray, Dufrene, Mercer, Olmi, and Sterling (2013) evaluated the effectiveness of DRA in young children and found that using DRA, along with pre-teaching an alternative behavior, had a significant impact on the behavior of the children [2]. This indicates that providing reinforcement for alternative behaviors can effectively decrease problem behaviors and promote positive behavior change.

Effectiveness of DRA in Young Children

In a study by Athens and Vollmer (2010), the effects of manipulating different variables of the reinforcer on the occurrence of problem behavior were evaluated. The researchers found that differentially reinforcing an appropriate alternative behavior improved outcomes [2]. This suggests that by reinforcing desirable behaviors, individuals are more likely to engage in those behaviors and reduce the occurrence of problematic ones.

Additionally, Vollmer, Iwata, Zarcone, Smith, and Mazaleski (1993) compared the effects of noncontingent reinforcement and differential reinforcement of other behavior (DRO). They found that noncontingent reinforcement could serve as an alternative to DRO and was preferred by the authors [2]. This highlights the importance of considering individual differences and preferences when implementing differential reinforcement techniques.

By examining these research studies, we can see the positive impact of differential reinforcement techniques, such as DRI and DRA, on skill acquisition and behavior modification. The findings support the use of these techniques in ABA therapy and interventions for individuals, especially young children, diagnosed with autism. Implementing DRI and DRA strategies tailored to the individual's needs and preferences can lead to significant improvements in behavior and overall well-being.

Practical Examples of Differential Reinforcement

To better understand how Differential Reinforcement of Incompatible Behavior (DRI) is implemented in ABA therapy, let's explore some practical examples and strategies. Additionally, we'll share success stories related to Differential Reinforcement of Alternative Behavior (DRA) techniques.

DRI Implementation Strategies

Implementing DRI involves identifying a behavior that is incompatible with the problem behavior and reinforcing it when it occurs, while withholding reinforcement for the problem behavior. Here are some strategies used in ABA therapy for implementing DRI:

DRA Success Stories

Differential Reinforcement of Alternative Behavior (DRA) has shown success in promoting positive behavior change in individuals receiving ABA therapy. Here are a couple of success stories that highlight the effectiveness of DRA:

These success stories demonstrate the power of DRA in promoting positive behavior change and improving the quality of life for individuals receiving ABA therapy. By reinforcing alternative behaviors that are incompatible with the problem behaviors, therapists and caregivers can effectively shape desired behaviors and reduce problem behaviors.

As we explore the various techniques and applications of differential reinforcement, it becomes evident that these strategies play a vital role in behavior modification and therapy. The next section will delve into the benefits of using differential reinforcement, including the impact on behavior modification success and the importance of positive behavior reinforcement.

Benefits of Using Differential Reinforcement

Differential reinforcement is a valuable strategy used in Applied Behavior Analysis (ABA) to address challenging or undesirable behaviors, especially in individuals with conditions like Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). By selectively reinforcing desired behaviors and withholding reinforcement for undesired behaviors, differential reinforcement promotes behavior modification success and positive behavior reinforcement.

Behavior Modification Success

The main goal of using differential reinforcement techniques is to achieve behavior modification success. By focusing on reinforcing specific behaviors while withholding reinforcement for others, individuals are motivated to engage in desired behaviors more frequently. This positive reinforcement approach encourages the development of adaptive skills and promotes behavior change across various settings, including schools, homes, therapy sessions, and workplaces. The versatility of differential reinforcement makes it a valuable tool in promoting positive behavior change [4].

Positive Behavior Reinforcement

Differential reinforcement relies on positive behavior reinforcement to shape and strengthen desired behaviors. Through the use of rewards, praise, or other forms of positive reinforcement, individuals are motivated to engage in behaviors that are desired or expected. This positive approach helps individuals understand what is expected of them, reinforces their efforts, and encourages the repetition of desired behaviors [5].

In contrast to punishment-based approaches, differential reinforcement focuses on promoting positive behaviors rather than solely focusing on eliminating negative behaviors. By reinforcing desired behaviors, individuals experience a sense of accomplishment and are more likely to continue engaging in those behaviors over time. This positive behavior reinforcement approach creates a supportive and encouraging environment for individuals to learn and grow.

By utilizing differential reinforcement techniques, professionals, parents, and educators can effectively shape behaviors, encourage skill development, and create long-lasting behavior change. The benefits of using differential reinforcement extend beyond the treatment of conditions like ASD and ADHD, making it a valuable strategy in promoting positive behavior change in individuals of all ages and abilities [4].

References


[2]:

[3]:

[4]:

[5]:

Understanding Differential Reinforcement

Differential reinforcement is a behavior modification technique used in Applied Behavior Analysis (ABA) that involves selectively reinforcing desired behaviors while withholding reinforcement for undesired behaviors. This approach aims to increase the occurrence of desired behaviors and decrease or eliminate problem behaviors. By using differential reinforcement, individuals can learn new, more adaptive behaviors [1].

Basics of Differential Reinforcement

Differential reinforcement involves the systematic application of positive reinforcement and negative reinforcement. Positive reinforcement refers to providing a pleasant stimulus after a behavior, which increases the likelihood of that behavior occurring again in the future. Negative reinforcement, on the other hand, involves removing an unpleasant stimulus after a behavior, also increasing the likelihood of that behavior being repeated.

The use of positive reinforcement and negative reinforcement is based on the principle that behaviors that are followed by a positive outcome or the removal of an aversive stimulus are more likely to recur in the future. By selectively reinforcing desired behaviors and not reinforcing undesired behaviors, individuals can learn to replace problem behaviors with more appropriate alternatives.

Types of Differential Reinforcement

There are several types of differential reinforcement techniques used in ABA therapy. These techniques focus on reinforcing specific behaviors to shape behavior change. Some common types of differential reinforcement include:

Each type of differential reinforcement has its own unique application and can be used based on the specific needs and goals of the individual undergoing ABA therapy.

Understanding the basics and types of differential reinforcement is essential to grasp the application and effectiveness of this behavior modification technique. In the subsequent sections, we will explore how differential reinforcement techniques, such as DRI, are utilized in ABA therapy and its role in autism intervention.

Differential Reinforcement Techniques

When it comes to differential reinforcement, there are various techniques used in Applied Behavior Analysis (ABA) therapy. These techniques aim to promote positive behavior change by utilizing different types of reinforcement. The key differential reinforcement techniques include positive reinforcement, negative reinforcement, differential reinforcement of alternative behavior (DRA), differential reinforcement of incompatible behavior (DRI), and differential reinforcement of other behavior (DRO).

Positive Reinforcement

Positive reinforcement involves providing a pleasant stimulus or reward following a desired behavior. This technique aims to increase the likelihood of the behavior occurring again in the future. By associating the behavior with a positive outcome, individuals are motivated to continue engaging in the desired behavior. Positive reinforcement can be implemented through the use of praise, tokens, tangible rewards, or access to preferred activities. To learn more about positive reinforcement in ABA therapy, refer to our article on positive reinforcement in ABA therapy.

Negative Reinforcement

Similar to positive reinforcement, negative reinforcement is a technique used to increase the occurrence of a desired behavior. However, it involves removing an unpleasant or aversive stimulus after the behavior occurs. This removal of the aversive stimulus serves as a reward, reinforcing the behavior. Negative reinforcement can be effective in motivating individuals to engage in the desired behavior to avoid or escape the aversive stimulus.

Differential Reinforcement of Alternative Behavior (DRA)

Differential reinforcement of alternative behavior (DRA) is a technique used to increase the occurrence of a desirable behavior while decreasing or eliminating an undesirable behavior. This involves reinforcing a behavior that serves as a suitable alternative to the problem behavior. For example, if a child engages in disruptive behaviors to gain attention, the DRA technique would involve reinforcing appropriate behaviors that achieve the same goal of gaining attention. By providing positive reinforcement for the alternative behavior, the individual is motivated to engage in the desired behavior instead of the problem behavior. Research has shown that DRA can be effective in promoting behavior change in typically developing children [2].

Differential Reinforcement of Incompatible Behavior (DRI)

Differential reinforcement of incompatible behavior (DRI) is a technique that focuses on reinforcing behaviors that are incompatible with the problem behavior. In other words, the individual cannot engage in both behaviors simultaneously. By reinforcing the incompatible behavior, the occurrence of the problem behavior is effectively reduced. For example, if a child engages in hitting behaviors when feeling frustrated, the DRI technique would involve reinforcing a behavior like using words to express frustration, which cannot be done while hitting. Research has indicated that the effectiveness of DRI is influenced by the functional relationship between the incompatible behavior and the problem behavior [2].

Differential Reinforcement of Other Behavior (DRO)

Differential reinforcement of other behavior (DRO) involves reinforcing the absence or non-occurrence of a problem behavior for a specified period of time. It focuses on reinforcing periods of time when the problem behavior does not occur. DRO can be effective when the goal is to decrease the frequency or duration of a specific behavior. For example, if a child engages in self-injurious behaviors, the DRO technique would involve providing reinforcement for any period of time when the child does not engage in self-injury. This technique helps to shape behaviors by reinforcing the absence of the problem behavior. Research has shown that DRO can be a preferred alternative to other differential reinforcement techniques [2].

By utilizing these differential reinforcement techniques in ABA therapy, behavior analysts can help individuals with autism and other developmental disorders acquire and maintain positive behaviors while reducing problem behaviors. The selection of the most appropriate technique depends on the individual's specific needs and the goals of the intervention.

Application of Differential Reinforcement

Differential Reinforcement of Incompatible Behavior (DRI) is a valuable technique utilized in Applied Behavior Analysis (ABA) therapy, particularly in the context of autism intervention. By focusing on reinforcing behaviors that are incompatible with problem behaviors, DRI aims to reduce unwanted behaviors and promote the development of more appropriate alternatives.

DRI in ABA Therapy

In ABA therapy, DRI is employed as a behavior modification strategy to address problematic behaviors, especially in children diagnosed with autism. The approach involves identifying a behavior that is incompatible with the problem behavior and reinforcing it while withholding reinforcement for the problem behavior. By doing so, the likelihood of the problem behavior occurring diminishes, and the desired behavior becomes more prominent.

For example, if a child engages in aggressive behaviors such as hitting others, a suitable replacement behavior that is incompatible with hitting, such as using words to express frustration, would be identified and reinforced. The reinforcement may come in the form of praise, rewards, or other positive stimuli tailored to the individual's preferences and needs.

Implementing DRI in ABA therapy requires careful observation, data collection, and collaboration between therapists, parents, and other caregivers. Through consistent and systematic application, DRI can be an effective tool in shaping behavior and fostering positive changes.

DRI in Autism Intervention

DRI holds particular relevance in the field of autism intervention due to its focus on promoting adaptive behaviors and reducing maladaptive ones. By targeting behaviors that cannot coexist simultaneously, DRI offers individuals with autism an opportunity to develop and engage in alternative behaviors that are more socially appropriate and functional.

Research has shown that DRI, along with other differential reinforcement techniques, can be effective in improving various skills and reducing problem behaviors in individuals with autism. For instance, a study examining the impact of DRI on skill acquisition found that using DRI resulted in increased appropriate behaviors and decreased inappropriate behaviors [3]. Another study explored the effectiveness of DRI in young children and found that it led to a significant decrease in problem behaviors and an increase in appropriate replacement behaviors [4].

By incorporating DRI into autism intervention programs, therapists and caregivers can effectively target and address specific behaviors, paving the way for skill development, enhanced communication, and improved social interactions.

Differential reinforcement techniques, such as DRI, play a vital role in ABA therapy and autism intervention. By harnessing the power of reinforcement to shape behavior, individuals with autism can make significant progress in their overall development, leading to improved quality of life and increased independence.

Research Studies on Differential Reinforcement

To understand the effectiveness and impact of differential reinforcement (DRI) in skill acquisition and behavior modification, several research studies have been conducted. These studies shed light on the benefits and outcomes of using DRI techniques in various settings, including ABA therapy and interventions for young children.

Impact of DRI on Skill Acquisition

Karsten and Carr (2009) conducted a study comparing different DRI procedures and their impact on skill acquisition. The researchers found that differentially reinforcing unprompted responses may lead to more rapid skill acquisition. This suggests that when individuals are encouraged and reinforced for independently demonstrating the desired behavior, their ability to acquire new skills may improve.

Differential reinforcement of alternative behavior (DRA) is another technique commonly used in ABA therapy. Legray, Dufrene, Mercer, Olmi, and Sterling (2013) evaluated the effectiveness of DRA in young children and found that using DRA, along with pre-teaching an alternative behavior, had a significant impact on the behavior of the children [2]. This indicates that providing reinforcement for alternative behaviors can effectively decrease problem behaviors and promote positive behavior change.

Effectiveness of DRA in Young Children

In a study by Athens and Vollmer (2010), the effects of manipulating different variables of the reinforcer on the occurrence of problem behavior were evaluated. The researchers found that differentially reinforcing an appropriate alternative behavior improved outcomes [2]. This suggests that by reinforcing desirable behaviors, individuals are more likely to engage in those behaviors and reduce the occurrence of problematic ones.

Additionally, Vollmer, Iwata, Zarcone, Smith, and Mazaleski (1993) compared the effects of noncontingent reinforcement and differential reinforcement of other behavior (DRO). They found that noncontingent reinforcement could serve as an alternative to DRO and was preferred by the authors [2]. This highlights the importance of considering individual differences and preferences when implementing differential reinforcement techniques.

By examining these research studies, we can see the positive impact of differential reinforcement techniques, such as DRI and DRA, on skill acquisition and behavior modification. The findings support the use of these techniques in ABA therapy and interventions for individuals, especially young children, diagnosed with autism. Implementing DRI and DRA strategies tailored to the individual's needs and preferences can lead to significant improvements in behavior and overall well-being.

Practical Examples of Differential Reinforcement

To better understand how Differential Reinforcement of Incompatible Behavior (DRI) is implemented in ABA therapy, let's explore some practical examples and strategies. Additionally, we'll share success stories related to Differential Reinforcement of Alternative Behavior (DRA) techniques.

DRI Implementation Strategies

Implementing DRI involves identifying a behavior that is incompatible with the problem behavior and reinforcing it when it occurs, while withholding reinforcement for the problem behavior. Here are some strategies used in ABA therapy for implementing DRI:

DRA Success Stories

Differential Reinforcement of Alternative Behavior (DRA) has shown success in promoting positive behavior change in individuals receiving ABA therapy. Here are a couple of success stories that highlight the effectiveness of DRA:

These success stories demonstrate the power of DRA in promoting positive behavior change and improving the quality of life for individuals receiving ABA therapy. By reinforcing alternative behaviors that are incompatible with the problem behaviors, therapists and caregivers can effectively shape desired behaviors and reduce problem behaviors.

As we explore the various techniques and applications of differential reinforcement, it becomes evident that these strategies play a vital role in behavior modification and therapy. The next section will delve into the benefits of using differential reinforcement, including the impact on behavior modification success and the importance of positive behavior reinforcement.

Benefits of Using Differential Reinforcement

Differential reinforcement is a valuable strategy used in Applied Behavior Analysis (ABA) to address challenging or undesirable behaviors, especially in individuals with conditions like Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). By selectively reinforcing desired behaviors and withholding reinforcement for undesired behaviors, differential reinforcement promotes behavior modification success and positive behavior reinforcement.

Behavior Modification Success

The main goal of using differential reinforcement techniques is to achieve behavior modification success. By focusing on reinforcing specific behaviors while withholding reinforcement for others, individuals are motivated to engage in desired behaviors more frequently. This positive reinforcement approach encourages the development of adaptive skills and promotes behavior change across various settings, including schools, homes, therapy sessions, and workplaces. The versatility of differential reinforcement makes it a valuable tool in promoting positive behavior change [4].

Positive Behavior Reinforcement

Differential reinforcement relies on positive behavior reinforcement to shape and strengthen desired behaviors. Through the use of rewards, praise, or other forms of positive reinforcement, individuals are motivated to engage in behaviors that are desired or expected. This positive approach helps individuals understand what is expected of them, reinforces their efforts, and encourages the repetition of desired behaviors [5].

In contrast to punishment-based approaches, differential reinforcement focuses on promoting positive behaviors rather than solely focusing on eliminating negative behaviors. By reinforcing desired behaviors, individuals experience a sense of accomplishment and are more likely to continue engaging in those behaviors over time. This positive behavior reinforcement approach creates a supportive and encouraging environment for individuals to learn and grow.

By utilizing differential reinforcement techniques, professionals, parents, and educators can effectively shape behaviors, encourage skill development, and create long-lasting behavior change. The benefits of using differential reinforcement extend beyond the treatment of conditions like ASD and ADHD, making it a valuable strategy in promoting positive behavior change in individuals of all ages and abilities [4].

References


[2]:

[3]:

[4]:

[5]: