What is TEACCH?   

The TEACCH® Autism Program is a clinical, training, and research program based at the University of North Carolina – Chapel Hill. TEACCH was developed by Dr. Eric Schopler and Dr. Robert Reichler in the 1960s. It was established as a statewide program in 1972 and has become a model for other programs around the world. 

TEACCH uses a method called “Structured TEACCHing.” This is based on the unique learning needs of people with ASD, including: 

• Strengths in visual information processing 
• Difficulties with social communication, attention and executive function 

Structured TEACCHing provides strategies and tools for teachers to use in the classroom. These help students with autism to achieve educational and therapeutic goals.  The Structured TEACCHing approach focuses on:  

• External organizational supports to address challenges with attention and executive function  
• Visual and/or written information to supplement verbal communication  
• Structured support for social communication 

This method supports meaningful engagement in activities. It also works to increase students’ flexibility, independence, and self-efficacy.   

Structured TEACCHing strategies can be used alongside other approaches and therapies.  

What Does TEACCH Look Like?  

TEACCH programs are usually applied in a classroom setting. TEACCH-based home programs are also available. Parents work with professionals as co-therapists for their children so that they can continue to use TEACCH techniques at home. 

Structured TEACCHing uses organization and supports in the classroom environment to help students learn best. This includes: 

1. Physical organization  
2. Individualized schedules 
3. Work (Activity) systems 
4. Visual structure of materials in tasks and activities 

Who Provides TEACCH Services?   

  TEACCH methods are used by a variety of autism professionals: 

• Special education teachers 
• Residential care providers 
• Psychologists 
• Social workers 
• Speech therapists 

What is the TEACCH Method?

The TEACCH method was developed by researchers who wanted a more effective and integrated approach to helping individuals with autism spectrum disorders (ASD). TEACCH is an evidence-based academic program that is based on the idea that autistic individuals are visual learners, so teachers must correspondingly adapt their teaching style and intervention strategies.

A Brief History

Autism is a lifelong developmental disability that affects an individual’s behavior and communication. Most people with autism struggle with language and function according to culturally normal social standards. People with autism may lack social awareness, emotional reciprocity and the ability to sustain conversations. There are currently different treatment and intervention models for autism, but evidence-based research is very limited. During the late 1970’s, the Treatment and Education of Autistic and Communication Handicapped Children (TEACCH) research program was formed at the University of North Carolina. Their continuing mission is to promote structured learning environments that encourage visual based engagement and communication.

The Five Basic Principles

TEACCH is centered on five basic principles. First, physical structure refers to individual’s immediate surroundings. Daily activities, such as playing and eating, work best when they are clearly defined by physical boundaries. Second, having a consistent schedule is possible through various mediums, such as drawings and photographs. Third, the work system establishes expectations and activity measurements that promote independence. Ideal work systems will communicate objectives with minimum written instructions. Fourth, routine is essential because the most important functional support for autistic individuals is consistency. Fifth, visual structure involves visually-based cues for reminders and instruction.

Common Misperceptions

There are many common myths and misperceptions about autism and the TEACCH method. One of the most common misunderstandings is that TEACCH is designed only for children. The TEACCH method works well with any individual with ASD. It is also not limited to those with intellectual disabilities, but individuals with ASD at all developmental levels. While the TEACCH method works best in self-contained classrooms, it can be implemented in any educational setting. Many people think that TEACCH programs are mainly for skills and structure, but they also promote language development. Some parents fear that TEACCH programs will isolate children with ASD, but it actually helps them to experience meaningful relationships and enjoyable social interactions.

Final Thoughts

Although the TEACCH method is based on scientific research and documented studies, there are several potential limitations. The existing research studies of the TEACCH programs show that no harm is done, but struggle to isolate statistical correlations. That is, most studies have lacked control groups, failed to use double-blind methods and suffered from small sample sizes. Teachers and parents support TEACCH because most ASD students experience progress, but it is difficult to pinpoint how the positive changes are directly correlated to the program. Most researchers feel that while more research is needed, TEACCH is a widely successful program that offers potential benefits. Individuals with ASD may also benefit from comparative interventions, such as Applied Behavioral Analysis.

The TEACCH method is a structured program that helps individuals with ASD learn, function and reach their goals.

What is Discrete Trial Teaching?

There is an increasing number of children who are diagnosed with autism, and Discrete Trial Teaching (DTT) is an important component of the interventions that doctors, therapists, and educators use with them. It is an important methodology that addresses the way these children learn new skills. What is DTT and how does it help children on the autism spectrum learn?

The Purpose of DTT 

Discrete Trial Teaching is an intervention method utilizing applied behavioral analysis. Many children on the more severe side of the autistic spectrum have deficits in learning basic abilities. DTT teaches skills through a structured ladder of small, easily-taught components. The method began in the 1970s through the efforts of Doctor Ivar Lovaas. Through repetition of the DTT process, children can obtain mastery over necessary abilities. The skills taught are classified as “cognitive, communication, play, social and self-help.”

There tends to be a lot of confusion between terms Discrete Trial Training (DTT) and Applied Behavioral Analysis (ABA). Often times when people talk about ABA programs for children with autism, they are actually referring to DTT. DTT is one of several types of teaching strategies that fall under the umbrella of ABA. So let’s tease the two apart.

ABA applies the science of “behaviorism,” to bring about meaningful change in an individual’s actions. It looks at behavior as a three step process:  the antecedent (a cue or instruction), the behavior and the consequence.

For example, when you’re hungry (antecedent), you eat something (behavior) and then you feel better (consequence). You enjoyed a positive consequence for your behavior, and this increases the likelihood that you’ll again eat when hungry in the future!

ABA applies this principle as an intervention to produce positive changes in behavior. Beyond the field of autism, it’s widely used to help individuals develop positive behaviors – such as good study habits. It’s also used to help those struggling with problem behaviors such as drug addiction.

In fact, most parents use a form of “ABA” on a daily basis, for example, by giving a child a “time out” for hitting or putting on a favorite movie after a child finishes his homework. Rewards and consequences can make a behavior more or less likely to happen again in the future. This relationship between the antecedent, behavior and consequence is what ABA is all about.

So how is DTT different?

DTT is a structured ABA technique that breaks down skills into small, “discrete” components. Systematically, the trainer teaches these skills one by one. Along the way, trainers use tangible reinforcements for desired behavior. For a child, this might include a candy or small toy.

 For example, a trainer teaching colors to a child might begin by teaching red. She would ask the child to point to red and then reward the behavior. She would then move on to teaching yellow by itself, reinforce that skill, and then ask about both colors. After the child learns all his colors, the trainer might teach the child to say each color’s name.

Many therapists have found DTT to be particularly effective for teaching skills to children with autism. DTT was one of the very first interventions developed for autism and has extensive research supporting it.

Are there other types of ABA that are effective for autism in addition to DTT?

Yes! Many of the effective early intervention approaches for autism are based on ABA principles, including the Early Start Denver Model (ESDM) and Pivotal Response Treatment (PRT). These are delivered in a more natural and less structured way than DDT. PRT is highly focused on whatever motivates the child. In PRT, for example, a child who is enjoying playing with a car and ramp might be asked to indicate a red versus blue car and then given the red car to roll down the ramp when he correctly points to it. ESDM similarly uses a natural environment but teaches multiple skills at once. So while teaching red, you may also be teaching turn-taking and other social skills.

All these types of ABA types of teaching include an instruction (antecedent), a response from the child (behavior), and a reward (consequence). The difference comes primarily in what types of rewards are used, and whether instructors use a highly structured format or use play and natural routines.

The 5 Principles of DTT

 The basics of DTT are stated in five principles. First, skills are broken down into small bites. Instructions are given in the most concise manner possible. Instead of asking a child to show the teacher which card on a table is red, the instructor may say simply, “touch red.” In this way, students avoid confusion about what the practitioner is asking. Second, the educator teaches each “bite” until the student masters it before moving on to another skill. Third, each session is intensive. Fourth, teachers begin with prompts as needed and then decrease them. Fifth, learning must be reinforced by incentives. The offering of these incentives and the point at which they are offered must be consistent. Dtteaching.com says that this early intervention technique is one of the main approaches therapists and educators use with children who exhibit autism.

What are the Training Steps of DTT?

There are five steps of DTT:

Discriminative Stimulus 

The discriminative stimulus is a brief clear instruction alerting the child to the task at hand. This helps the student make a connection between a specific direction and an appropriate response. An example could be when a teacher says: “what is this?” before asking a child to identify an object.

The Prompt

A prompt is not always given but, for some children, it may be necessary to help them form the proper response. When provided, it is performed between the discriminative stimulus and the response. A prompt is when the teacher shows the child the correct response to guide their behavior. For example, using the above example, a trainer may tap the correct object if it appears the child is having difficulty.

Child Response

The response is the behavior the child exhibits when presented with the discriminative stimulus. It is either going to be correct or incorrect. The target response is clearly defined ahead of time so the trainer knows exactly what behaviors are considered correct.

Consequence

 The consequence will vary according to the correctness of the response:

• Correct Response: A correct response is immediately reinforced with a positive reward. Often, the child is shown the reward ahead of time to know what they will be receiving. The reward may be verbal praise, food (e.g., a piece of candy), or a token from a behavioral modification system (e.g., a star that goes toward whatever they are earning). Whatever the reward, the type and amount are clearly specified before each trial.

• Incorrect Response: When a child gives an incorrect response during a DTT trial, they are simply corrected. The trainer tries to remain as neutral as possible and gives no reinforcement or punishment. For example, a teacher may point at the correct answer and say: “let’s try the next one”.

Inter-Trial Interval

The inter-trial interval is the last step of DTT. It is the period of time that occurs after the consequence. It indicates the end of one trial and the impending start of another. It is usually no more than five seconds. The shortness of the interval contributes to the continuity of the learning process.

How is DTT Different?

DTT is only one type of training that uses applied behavioral analysis. For instance, another teaching protocol, Incidental Teaching, focuses on naturally occurring events as teaching opportunities. The practitioner arranges an environment attractive to children and allows the child to prompt the teaching by showing interest in someone or something around him. The instructor then “elaborates” on the chosen item and elicits responses from the student. When the child reacts appropriately, he receives a “confirming response” or, in other words, a reward.

In Discrete Trial Teaching, however, the learning opportunity is engineered and structured by the practitioner. The process is as follows:

• Acquisition: the child accomplishes the initial lesson.

• Fluency: the child demonstrates the ability to repeat the skill and mastery of it.

• Maintenance: the student maintains the ability to perform the skill over time.

• Generalization: The child can apply the skill to a different environment or area.

Another difference between DTT and other types of ABA training is that sessions are more intensive than those in Incidental Teaching. This is because there are numerous quick sessions with very little lag time between trials. There is also the factor of social relevancy. Although a skill must be relevant for a child to want to learn it, DTT engineers sessions that teach skills that can be used in the environment whether or not they are needed in the instant. Incidental Teaching, in contrast, imparts skills as the need for them arises. In either method, the reward must be something which the child values, and it must be given immediately after the child learns the task.

The Value of DTT

As we learn more about autism, we will discover more and better ways to teach children how to communicate and interact in society to give them more normalcy in their lives. We now say that children “fall on the autism scale,” which is a way of saying that there are varying degrees of the condition. Any training method has to adapt to the level of cognition and communication the student possesses. Discrete Trial Teaching is an attempt to give children skills important to daily living that can be configured to the abilities of the student preparing them to have the fullest life possible.

In short, DTT is a concise step-by-step intervention tailored to improve a specific skill in the most efficient way possible. Its concentration on positivity and brevity allows for the productive shaping of important behavior in an easy-to-digest format. It has been a crucial intervention in assisting the autistic community for almost 50 years.

What is Pivotal Response Treatment?

Pivotal Response Treatment, or PRT, is a behavioral treatment for autism. This therapy is play-based and initiated by the child. PRT is based on the principles of Applied Behavior Analysis (ABA).

Goals of this approach include:

• Development of communication and language skills
• Increasing positive social behaviors
• Relief from disruptive self-stimulatory behaviors

The PRT therapist targets “pivotal” areas of a child’s development instead of working on one specific behavior. By focusing on pivotal areas, PRT produces improvements across other areas of social skills, communication, behavior and learning.

Pivotal areas include:

• Motivation
• Response to multiple cues
• Self-management
• Initiation of social interactions

Motivation strategies are an important part of the PRT approach. These emphasize natural reinforcement.

For example, if a child makes a meaningful attempt to request a stuffed animal, the reward is the stuffed animal – not a candy or other unrelated reward. Children are rewarded for making a good attempt, even if it is not perfect. 

PRT was developed by Dr. Robert L. Koegel and Dr. Lynn Kern Koegel of Stanford University. It was previously called the Natural Language Paradigm (NLP). This approach has been used since the 1970s.

Who provides PRT?

A variety of providers seek training in PRT methods, including:

• Psychologists
• Special education teachers
• Speech therapists

What is a typical PRT therapy program like?

Each program is tailored to meet the goals and needs of the individual person and his or her everyday routines.

A session typically involves six segments. Language, play and social skills are targeted with both structured and unstructured interactions.

The focus of each session changes as the person makes progress, to accommodate more advanced goals and needs.

PRT programs usually involve 25 or more hours per week.

Everyone involved in the child’s life is encouraged to use PRT methods consistently in every part of his or her life. PRT has been described as a lifestyle adopted by the whole family.

What is Pivotal Response Treatment?

One of the most proven behavioral approaches for treating children with autism spectrum disorders is pivotal response treatment, or PRT. Drawn from applied behavior analysis, PRT is a play-based method that targets improving “pivotal” development areas instead of individual behaviors. It’s based on the idea that changes in pivotal responses would spark widespread progress in other developmental areas. PRT was initially established in the 1970s by Dr. Robert Koegel and Dr. Lynn Kern Koegel at the University of California- Santa Barbara. First called pivotal response teaching, PRT combined several research-based interventions to improve autistic children’s social and communicative growth. A study published in Behavior Modification journal showed that pivotal response treatment is highly effective for preschool, elementary, and middle school students with ASD.

Four Main Pivotal Areas Targeted

Pivotal response treatment strives to thwart negative, self-stimulatory behaviors associated with autism by addressing four main “pivotal” areas. The central area is motivation. PRT therapy works to increase children’s desire to learn and perform skills associated with good consequences. Rather than force tasks, PRT uses the child’s interests to reinforce pro-social behaviors and trigger enthusiasm. The second “pivotal” area is initiations. PRT encourages the child to initiate social interaction by asking questions or obtaining attention. Next comes self-regulation. This “pivotal” area teaches children to self-evaluate and discriminate their behaviors for greater independent. Finally, PRT trains autistic youth to respond to multiple cues rather than focus on specific details or stimuli.

What’s Involved in PRT Sessions

PRT therapy sessions involve using positive reinforcement to address the above “pivotal” areas, which will result in broad progress for sociability. Pivotal response treatment is customized to meet the unique needs of individual children and their routines. Most school-based PRT programs will consist of 25 or more hours weekly. Parents or guardians should also adopt PRT methods in the home environment for consistency. Pivotal response treatment uses play therapy to target social skill development, so unstructured interactions are common. Lessons could include taking turns, imitation, joint attention, or peer interaction. For example, if the child verbally expresses a desire for a doll, they’ll be rewarded with the toy.

Qualifications to Provide PRT Therapy

Practitioners of pivotal response treatment typically need special certification beyond their training and licensing. PRT is most often provided by school psychologists, special education teachers, speech-language pathologists, and occupational therapists. Some applied behavior analysts may dabble in PRT therapy since it’s derived from ABA. Most PRT providers attain at least a master’s degree in counseling, psychology, education, or therapy. Accredited master’s programs will require clinical practicum to satisfy the contact hours for licensing, which varies greatly by state and title. After licensing, providers should pursue certification from the UCSB Koegel Autism Center. Three levels of PRT certification can be obtained with workshops. Level I Certification requires attending the two-day Pivotal Response Treatment Conference.

Overall, pivotal response treatment was recognized by the National Research Council as one of the top 10 model programs for autism. Motivation strategies utilized in PRT therapy helped 85% of toddlers with autism develop verbal language as their primary communication. PRT is an evidence-based behavioral approach targeting critical behaviors in natural environments for better social skills. As the diagnosis of children with ASD grows more prevalent, pivotal response treatment is expected to become a leading form of early intervention.

Pivotal Response Training (PRT) is a variation of Applied Behavioral Analysis (ABA) type therapy. It focuses on more comprehensive “pivotal” areas such as increasing a child’s motivation to learn, initiate communication, and monitor their own behaviors. This focus on motivation is crucial: a child who is motivated to change their behavior will experience more success. By focusing on critical over-arching areas, the effects of treatment can carry over into many aspects of a child’s behavior and skills including social, communicative, and academic.

In order to motivate children, PRT is typically play-based and the therapist lets the child initiate activities such as what game to play, what to talk about, or what to learn. Tasks are varied and children are given natural reinforcers that relate to the current situation: such as asking appropriately for a toy and then being handed that toy.

Pivotal Response Training (PRT) is a naturalistic intervention model based in Applied Behavior Analysis. Rather than target individual behaviors one at a time, PRT targets pivotal areas of a child’s development, such as motivation, responsivity to multiple cues, self-management, and social initiations. By targeting these critical areas, PRT results in widespread, collateral improvements in other social, communicative, and behavioral areas that are not specifically targeted. Underlying motivational strategies are incorporated throughout intervention including: choices, task variation, interspersing maintenance tasks, rewarding attempts, and the use of direct and natural reinforcers. The child plays a crucial role in determining the activities and objects that will be used in the PRT exchange. Intentful attempts at the target behavior are rewarded with a natural reinforcers (e.g. if a child attempts a request for a stuffed animal, the child receives the animal, not a piece of candy or unrelated reinforcer). PRT is used to teach language, decrease disruptive/self- stimulatory behaviors and increase social, communication, and academic skills.

D-6: DESCRIBE RATIONALES FOR CONDUCTING COMPARATIVE, COMPONENT AND PARAMETRIC ANALYSES ©

Target Terms: Comparative Analysis, Component Analysis, Parametric Analysis 

Comparative Analysis 

Definition: A type of analysis used to compare two different types of treatments, such as a multielement/alternating treatment design. 

Component Analysis

Definition: An experiment designed to identify which part of the treatment package is responsible for behavior change. 

Drop-Out Component Analysis: An experiment where the investigator presents the treatment package and then systematically removes components. 

Example in clinical context: A behavioral analyst is using an intensive feeding intervention with a client. They present all the components of the intensive feeding intervention and begins to eliminate components to determine if there are any effects on the client’s behavior (e.g., removal of response cost for packing or expulsion of food while keeping positive reinforcement in place). 

Add-In Component Analysis: An experiment where the investigator assesses components of a treatment package individually or in combination before the treatment package is delivered.

Example in supervision/consultation context: A behavior analyst presents a treatment package to a supervisor that is used to target employee productivity. The behavior analyst and supervisor review each component and choose to add in additional components based on the needs of the organization. 

Why it matters: Component analyses make sense when trying to isolate which aspects of a plan are having the most impact on an observed change. 

Parametric Analysis

Definition: An experiment designed to evaluate the range of values for an intervention. (This type of analysis is sometimes called a “sensitivity analysis” in other fields, which can hep to remember what it means.) The idea is to determine the effect of changing one or more dimensions of an independent variable along a continuum, rather than the variable itself.

Example in clinical context: A psychiatrist and behavioral analyst are examining the effects of Clonidine on a patient’s attentiveness and hyperactivity. They begin to evaluate the effects of a 0.10mg dosage and then evaluate the effects of a 0.05mg dosage. They find that the patient’s attentiveness and hyperactivity was sustained at 0.05mg. 

Example in supervision/consultation context: A supervisor consults with a behavior analyst because they want to evaluate how long of a lunch break they should provide to their employees to increase their afternoon work production. The behavior analyst provides employees with a 90-minute break and then a 60-minute break. They found that afternoon production increased when the employees had a 90-mintue lunch break rather than a 60-minute lunch break. 

Why it matters: Parametric analyses seek to understand the value of an independent variable to determine which of those values are the most effective for the intervention. 

Comparative Analysis

A comparative analysis analyzes two different types of treatments (learningbehavioranalysis.com).

     Question: Did "Intervention A" or "Intervention B" work better?

Comparative Analysis

Component Analysis

A component analysis analyzes pieces of a treatment package to determine which piece is influencing the dependent variable (learningbehavioranalysis.com).

     Question: Within the intervention package, which part worked the most?

Component analysis

Parametric Analysis

A parametric analysis evaluates the effects of different dosages of a treatment on the dependent variable (learningbehavioranalysis.com).

     Question: What amount of the intervention (or drug) is most effective?

Parametric analysis

D-5: USE SINGLE-SUBJECT EXPERIMENTAL DESIGNS (E.G., REVERSAL, MULTIPLE BASELINE, MULTIELEMENT, CHANGING CRITERION) ©

Target Terms: Reversal (A-B-A-B) Design, Multiple Baseline Design, Multielement/Alternating Treatment Design, Changing Criterion Design 

Reversal (A-B-A-B) Design 

Definition: An experimental design where baseline conditions (A) and an intervention conditions (B) are reversed with the goal of strengthening experimental control (i.e. demonstrating that the change in the dependent variable is due to the change in the independent variable).

Example in clinical context: A behavior analyst collects baseline data (A) on a student’s tantrum behavior. They begin to implement an intervention (B) and collects data on the student’s tantrum behavior. After several trials of the intervention, the behavior analyst withdrawals the intervention, waits for responding to stabilize, and again implements the intervention.

Example in supervision/consultation context: A behavior analyst is consulting in a classroom where they are providing support to the paraprofessionals in the room. The behavior analyst collects baseline data (A) on the paraprofessional’s use of specific praise, and begins to implement an intervention (B) which targets a increase in specific praise behavior using visual and auditory prompts for staff. The behavior analyst withdrawals the intervention, and rates of the target behavior return to baseline rates. The behavior analyst reinstates the intervention and finds that the use of specific praise once again increases. 

Why it matters: Reversal designs are a powerful single-subject design for demonstrating a functional relation between an independent and dependent variable. Reversal designs involve prediction, verification and replication. There are several variations of reversal designs depending on the severity of the target behavior or type of reinforcement schedule used. One major limitation of A-B-A-B designs is that they are not suitable for a target behavior that cannot be “unlearned;” for example, teaching someone to read and then withdrawing the intervention would not result in a loss of existing reading ability.

Multiple Baseline Design

Definition: An experimental design where implementation of the intervention is staggered in a stepwise fashion across behaviors, settings, and subjects. 

Example in clinical context: A behavior analyst wants to target a student’s dropping behavior in two different settings: the classroom and in the hallway. The behavior analyst begins to collect baseline data on the dropping behavior in both settings. After a steady state of responding is demonstrated, the behavior analyst implements the intervention in the first setting, the classroom, while holding the hallway in baseline. After steady responding is achieved in the first implementation setting, the intervention is applied to the second setting which is the hallway.

Example in supervision/consultation context: A behavioral analyst is consulting for a small company that has a uniform set of goals for employees to achieve. They conduct a multiple baseline design on one of these goals for five employees. The behavior analyst begins to collect baseline data for all five employees. After a steady state of responding is achieved for all five employees, the behavior analyst implements an intervention to address the first employee goal on the first employee while holding the other four employees in baseline. After a steady state of responding is achieved with the first employee, the behavior analyst implements the intervention with the second employee and follows this stepwise fashion with all employees. 

Why it matters: Multiple baseline designs are the most widely used design due to their flexibility. They do not require the withdrawal of a treatment variable. Multiple baseline designs involve prediction, verification and replication. There are variations of the multiple baseline design. 

Multielement/Alternating Treatments Design

Definition: An experimental design where two or more conditions are presented in rapidly alternating succession independent of the level of responding and the effects on the target behavior. 

Example in clinical context: A behavior analysts is comparing two treatments with a client on the response rate of their aggressive behavior. The behavior analyst conducts a multielement/alternating treatments design on Treatment A and Treatment B. Treatment A did not appear to have an effect on the aggressive behavior, but Treatment B showed a sharp decrease in aggressive behavior.

Example in supervision/consultation context: A supervisor is comparing two types of supervision modalities to determine which one is more effective in teaching ABA concepts. The supervisor conducts a multielement/alternating treatments design with their supervisee on supervision types 1 and 2. The first, Type 1, was correlated with a significant amount of change in the supervisee’s knowledge, whereas Type 2 did not demonstrate any change. The supervisor concludes Type 1 is likely to be a more effective means of teaching novel concepts for this supervisee. 

Why it matters: Multielement/Alternating treatments designs are used to evaluate which independent variable would be best to utilize with a client. They do not require withdrawal of the intervention and can be used to quickly make comparisons between treatment conditions. Multielement/Alternating treatment designs involve prediction, verification and replication. There are several variations of the multielement/alternative treatment designs including with or without baseline. 

Changing Criterion Design 

Definition: An experimental design where the initial baseline phases are followed by a series of treatment phases consisting of successive and gradual changing criteria for reinforcement or punishment. 

Example in clinical context: A behavior analyst wants to assess how a client’s behavior changes when they provide reinforcement for every five responses per minute, then ten responses per minute and so on. The criterion increases as the client demonstrates stable states of responding.  

Example in supervision/consultation context: A behavior analyst is consulting with a client who wants to decrease the number of cigarettes they smoke per day with the goal of quitting. The client currently smokes 16 cigarettes per day. The first criterion the behavior analyst sets before the client can earn reinforcement is 13 cigarettes per day, to 10, seven, five and one. The criteria decrease as the client demonstrates stable states of responding. 

Why it matters: Changing criterion designs can only be used when the behavior is already in the learner’s repertoire. They do not require reversal or withdrawal of treatment. Changing criterion designs do not allow for comparison. They also involve prediction, verification and replication. Experimental control is demonstrated by the extent to which the level of responding changes in response to each new criterion.

Reversal Design

A reversal design is a type of study in which the researcher implements one phase, introduces the second phase (reversal), and then reintroduces the conditions of the first phase. (Cooper, Heron, and Heward, 2007).

     Examples: A-B-A design, B-A-B design

Reversal design

Multiple Baseline Design

A multiple baseline design measures the effect of the independent variable on two or more dependent variables by systematically introducing the treatment in delayed intervals (Cooper, Heron, and Heward, 2007). There are three types of multiple baseline design:

- Multiple baseline across behaviors

- Multiple baseline across settings

- Multiple baseline across participants

Alternating Treatments Design

An alternating treatments design measures the effectiveness of two or more independent variables on a dependent variable by alternating each of the treatment conditions (Cooper, Heron, and Heward, 2007).

Multielement Design

Multielement design is a term that is sometimes used in literature to describe an alternating treatments design (Cooper, Heron, and Heward, 2007).

Changing Criterion Design

A changing criterion design uses stepwise adjustments in criteria for a target behavior in order to demonstrate increasing or decreasing effects due to the independent variable. (Cooper, Heron, and Heward, 2007).

Changing criterion design

Leave us a comment with a link to a graph demonstrating one of these designs!

D-4: DESCRIBE THE ADVANTAGES OF SINGLE SUBJECT EXPERIMENTAL DESIGNS COMPARED TO GROUP DESIGN ©

Group Design

Group design involves randomly assigning participants to two (or more) groups with at least one treatment group and one control group. Data from each group are compared (Cooper, Heron, and Heward, 2007).

Group Design Advantages

- Averages in data among groups may help account for variability (Cooper, Heron, and Heward, 2007).

- Usually larger number of participants in the study, which can improve external validity (Cooper, Heron, and Heward, 2007).

Group designs involve a control group and have some advantages compared to single-subject designs.

Single-Subject Experimental Design Advantages

- Better represents individual participants (Cooper, Heron, and Heward, 2007)

- Reveals individual variability (Cooper, Heron, and Heward, 2007)

- Replication of findings in individual participants (Cooper, Heron, and Heward, 2007)

To learn more about single-subject experimental designs, go check out our previous blog post!

Single-subject designs have some advantages too.

Leave us a comment and tell us if you think group designs or single-subject designs are better!

D-3: IDENTIFY DEFINING FEATURES OF SINGLE-SUBJECT EXPERIMENTAL DESIGNS (E.G., INDIVIDUALS SERVE AS THEIR OWN CONTROLS, REPEATED MEASURES, PREDICTION, VERIFICATION, REPLICATION)©

Single-Subject Experimental Design

In a single-subject experimental design, the baseline data is used to demonstrate changes in a target behavior or dependent variable due to manipulation of the independent variable (Cooper, Heron, and Heward, 2007).

     Examples: A-B design, A-B-A-B design, multiple baseline design, alternating treatments design, and changing criterion design

A-B design : Baseline condition (A) and treatment condition (B). Does not show experimental control.

A-B-A-B (baseline, IV, baseline again, IV again) § Preferred because we reintroduce the B condition which enables the replication of treatment effects, which strengthens the demonstration of experimental control

multiple baseline design :

- Presentation of multiple baselines in order to be an alternative to reversal designs

-  Allow practitioners to analyze the effects of an independent variable across multiple behaviors, participants or settings without having to withdraw the treatment variable to 20 verify that the improvements in behavior are a direct result of the application of the treatment.

- Verification is established when you add a baseline, and replication is established when the results are replicated with another individual/setting/or behavior.

- 3 to 5 tiers are most common 

- Introduction of the IV is always done after a stable baseline

Advantages of multiple baselines:

1. Does not require withdrawing treatment

2. Good for evaluation of progressive, multiple behavior changes sought by many practitioners

Limitations of multiple baseline designs

1. May not allow for a demonstration of experimental control even though a functional relation exists between the IV(independent variable) and the DV(dependent variable)

2. Weaker method for showing experimental control 21

3. Provides more information about the effectiveness of the treatment variable than it does about the function of any particular target behavior

alternating treatments design

Changing criterion Design

- Can be used to evaluate the effects of a treatment that is applied in a graduated or stepwise fashion to a single target behavior

- Requires initial baseline observations on a single target behavior 

- Then it is followed by implementation of a treatment program in each of a series of treatment phases

- Each treatment phase is associated with a step-wise change in criterion rate for the target behavior

- Each phase of the design serves as a baseline for the following phase 

- Requires careful manipulation of three factors § Length of phases

         • Requires stable responding § Magnitude of criterion changes

         • There must be a change in level § Number of criterion changes

         • The more the better the experimental control

Control(s)

In single-subject designs, each participant serves as their own control. This means that the effects of each condition are compared to the participant's own data (Cooper, Heron, and Heward, 2007).

     Example: Participants in a study are working to increase their running distance over time. The researchers use a changing criterion design. They first take baseline data on the participants and then gradually increase the required distance for runners to receive reinforcement in stepwise phases over the course of the study.

Runners could serve as their own controls in a changing criterion design.

Repeated Measures

In single-subject designs, each participant's target behavior or dependent variable is measured in every condition of the study which results in repeated measures (Cooper, Heron, and Heward, 2007).

     Example: Even in the most simple of single-subject research designs, an A-B design, the dependent variable is still measured twice: Once in the baseline phase, once in the intervention phase.

Single-subject research designs utilize repeated measures.

Prediction

Prediction is the hypothesis regarding what the outcome of a measurement will be in a study (Cooper, Heron, and Heward, 2007). Also, can the researchers determine what will happen to the dependent variable based on effects from previous phases due to the manipulation of independent variable?

Verification

Verification involves demonstrating that baseline data of the dependent variable would have remained consistent if the independent variable had not been manipulated (Cooper, Heron, and Heward, 2007).

Replication

Replication involves demonstrating similar results in an additional phase (or phases) when repeating the manipulation of the independent variable (Cooper, Heron, and Heward, 2007).

Replication: Showing the same or similar results in additional phases or with repeated manipulations of the independent variable

Leave us a comment with a link to a research study that utilizes single-subject research!

D-2: DISTINGUISH BETWEEN INTERNAL AND EXTERNAL VALIDITY ©

Target Terms: Internal Validity, External Validity 

Internal Validity

내적타당도 : 실험적 연구에 있어서 주어진 실험처치(experimental treatments)가 정말로 실험효과를 가져왔느냐 하는 정도. 이 내적 타당도에서는 주어진 실험처치가 이 실험에서 정말로 어느 정도 실험효과를 가져왔느냐에 대한 질문의 답이 된다. 한 실험연구의 내적 타당도는 필수적인 요건이 되며, 이러한 내적 타당도를 높이기 위해서는 다른 잡다한 요인들이 종속변인에 우연적으로 영향을 주는 일이 없도록 실험연구를 잘 통제해야 될 것이다.

Definition: An experiment shows convincingly that changes in behavior are a function of the intervention/treatment and NOT the result of uncontrolled or unknown factors. 

Example in clinical context: A behavior analyst implements a DRA procedure to support a client who engages in skin picking. The skin picking behavior responds favorably to the intervention. When the DRA is removed, the target behavior returns. When the intervention is put in place a second time, the behavior returns to low rates. This fact pattern strongly suggests that the DRA intervention (and nothing else) was primarily responsible for the reduction in skin picking behavior. 

Example in supervision/consultation context: A behavior analyst is consulting in a classroom and implements a direct instruction methodology during literacy time. No other classroom or homework practices are altered. After several weeks of receiving this new instruction, the students show significant improvement in their reading performance. The behavior analyst concludes that the instructional method is the reason why the student’s academic performance is improving and is not the result of uncontrolled variables. 

Why it matters: Without high internal validity, cause-and-effect relationships cannot be discovered.

Behavior analytic literature places an emphasis on within-subjects designs, wherein research participants serve as their own controls. This is a fantastic way of answering clinical questions about individuals. When applying behavior analytic research to our own work, we carefully select findings that have direct bearing on our own clinical problems (for example, by matching the function of problem behavior).

However, because behavior analytic studies usually have small numbers of participants, and because we tend not to use between-subjects (groups) designs, it can take longer to build external validity, and our work can be confusing to other fields which rely on large numbers of participants to “even out” individual variables.

External Validity 

외적타당도 : 외적 타당도란 이 실험결과를 어느 정도 일반화할 수 있느냐에 대한 답이 된다. 

Definition: The degree which a study’s results are generalizable to other subjects, settings and/or behaviors not included in the original study. 

Example in clinical context: A behavior analyst is implementing a new intervention from a study that they read in a peer reviewed journal. The individual participant variables (developmental level, topography and function of behavior, for example) are a good match with the behavior analyst’s current client. The analyst replicates the intervention steps with their client and achieves similar favorable results. This supports the study’s external validity, since the results from the study have been replicated with a different subject. 

Example in supervision/consultation context: A study is conducted on a systematic way to teach consultees how to conduct functional assessments independently. All subjects in the study learned to complete functional assessments using the methods described in the study. Subsequently, numerous other studies replicated the methods and found similar results across participants and settings. This is strong evidence in support of the original study’s external validity.

Why it matters: Research findings are clinically useless unless they can convincingly demonstrate (1) that the methods were responsible for the observed changes, and (2) that the methods can work across participants and contexts not included in the original study. Science is always building and correcting itself, and replication is a vital – if unglamorous – part of the scientific process!

Internal Validity

Internal validity is the degree to which the changes in the dependent variable truly result from the manipulation of the independent variable and not from other causes (Cooper, Heron, and Heward, 2007).

     Questions to ask yourself: Did the study control for confounding and extraneous variables to an acceptable degree? Could the results have been caused by other unknown events or influences? 

Internal Validity

External Validity

External validity is the degree to which the results yielded by the study can be generalized to other target behaviors, populations, etc. (Cooper, Heron, and Heward, 2007).

     Questions to ask yourself: Would the results of this study likely be similar or not in other populations of individuals? Would the results likely be similar or not in other settings? Would the results likely be similar or not if related behaviors were studied using the same or similar independent variables?

External Validity

D-1: DISTINGUISH BETWEEN DEPENDENT AND INDEPENDENT VARIABLES ©

Target Terms: Dependent Variable, Independent Variable 

Dependent Variable 

Definition: The target behavior which the intervention is designed to change. It depends on the environment to change it.

Example in clinical context: A client’s eloping behavior which is targeted for intervention. 

Example in supervision/consultation context: Employee weekly productivity reports. 

Why it matters: The dependent variable must be identified if the goal is to produce change in behavior. 

Independent Variable

Definition: The intervention designed to have an effect on the dependent variable. The independent variable intervenes on the phenomenon of interest.

Example in clinical context: Response blocking as a means to prevent elopement. 

Example in supervision/consultation context: Positive reinforcement earned when employees make their weekly productivity goal. 

Why it matters: In order to accurately understand behavior change, all change targets and treatment conditions must be identified. Though we may not be actively involved in publishing research, our work with clients must be driven by an empirical process.

Independent Variable

An independent variable is the variable that is manipulated in order to observe the effect on the dependent variable. It is the treatment or intervention being studied (Cooper, Heron, and Heward, 2007).

     Example: In a study, researchers examine the effect of non-contingent reinforcement in the form of participation grades on the amount of homework completed. The non-contingent reinforcement (participation grade) is the independent variable.

     Question to ask yourself: What intervention or treatment is being studied?

Dependent Variable

A dependent variable is a variable that is measured in order to observe the effect that the independent variable has on it. In ABA, it is the target behavior (Cooper, Heron, and Heward, 2007).

     Example: In a study, researchers examine the effect of non-contingent reinforcement in the form of participation grades on the amount of homework completed. The amount of homework completed is the dependent variable.

     Question to ask yourself: What behavior, symptom, skill, or other variable is being measured?

C-11: INTERPRET GRAPHED DATA ©

Target Terms: Level, Variability, Trend

Level 

Definition: The value of a data point along the x-axis of a graph. 

Example in clinical context: A behavior analyst is conducting visual analysis of a client’s target behavior of head to wall self-injury. The behavior analyst determines the level by locating the number along the x-axis to the data points within the graph. The behavior analyst observes that the level of data points are located around the 10% interval along the x-axis.  

Why it matters: Examining the level of a data point is a skill in visual analysis that allows the behavior analyst to determine how much or little a behavior has changed. 

Variability 

Definition: The extent to which the data move around on the graph.

Example in clinical context: A behavior analyst is conducting visual analysis of a client’s target behavior of dropping to the floor. The data path is scattered all around the graph. This shows a high degree of variability in the client’s dropping behavior. 

Why it matters: Variability demonstrates the consistency to which change is taking place. A high variability may demonstrate a low degree of control of an intervention condition, whereas a low variability may demonstrate a high degree of control of an intervention condition. (In other words, if data points are all over the place, there is probably something else going on that has not been accounted for yet.)

Trend

Definition: The overall direction of the data path. 

Example in clinical context: A behavior analyst is conducting visual analysis on a client’s hitting behavior. They observe that the data path is increasing in trend. 

Why it matters: Examining trend provides us with information about the “bigger picture” of where a behavior is heading based on past responding. It is helpful as part of intervention planning and evaluation.