RBT Task List – Assessment (B-01)

While Registered Behavior Technicians (RBTs) do not design or independently conduct comprehensive assessments, they play a vital and active supportive role in the assessment process under the close supervision of a BCBA or BCaBA.

This section will detail how RBTs contribute to various assessment activities. It’s crucial to remember that your role is to implement these procedures with precision and fidelity, and to report your findings accurately.

Interpretation of results and diagnostic conclusions fall under the purview of your supervisor.

Let’s begin with one of the most common and foundational assessment-related tasks for RBTs:

B-01: Conduct Preference Assessments

Clear Explanation: What is a Preference Assessment?

A preference assessment is a set of systematic procedures used to identify stimuli (e.g., specific items, activities, types of edibles, forms of social interaction) that an individual shows a preference for.

The primary goal of conducting a preference assessment is to identify potential reinforcers stimuli that, when delivered contingent upon a behavior (meaning, delivered right after the behavior occurs and only if it occurs), will increase the future likelihood of that behavior occurring again.

It’s important to emphasize that a preference assessment identifies potential reinforcers.

While highly preferred items are good candidates, a separate process, known as a reinforcer assessment (often conducted by the BCBA, sometimes with RBT assistance), is needed to formally confirm if a highly preferred item actually functions to strengthen behavior when used as a consequence.

RBTs are frequently tasked by their supervisors to conduct various types of preference assessments. Why? Because understanding what an individual likes and is motivated by is fundamental to:

• Creating motivating learning environments.
• Developing effective reinforcement systems for teaching new skills and increasing desired behaviors.
• Individualizing interventions effectively.

Preferences can change over time and across different contexts (e.g., what’s preferred in the morning might differ in the afternoon; what’s preferred at home might differ at school).

Therefore, preference assessments may need to be conducted regularly.

Why are preference assessments so important?

• Identify Potential Reinforcers: They provide an empirically-based, data-driven way to make educated guesses about what might work as a reward, rather than just assuming.
• Increase Client Motivation: Using items and activities that the client genuinely prefers can make learning tasks more enjoyable and significantly increase their engagement and participation.
• Individualize Interventions: What one person loves, another might dislike or be indifferent to. Preference assessments respect and honor these individual differences.
• Avoid “Guessing Games”: Relying on assumptions or anecdotal reports about what a client likes can be inefficient and lead to frustration for both the client (if they’re not motivated) and the RBT (if teaching isn’t effective).
• Combat Satiation: By identifying a range of preferred items and activities, RBTs and BCBAs can vary reinforcers.
  This helps prevent the client from getting “tired” or satiated on a single item, which would reduce its effectiveness as a reinforcer.

Detailed Breakdown of Common Preference Assessment Methods Implemented by RBTs

Supervisors will select the specific preference assessment method based on factors like the client’s communication skills, their ability to make choices, the time available for the assessment, and the type of information needed. RBTs must be able to implement these methods precisely as instructed.

Ask-Based Methods (Indirect Preference Assessments)

These methods involve asking the client directly or asking significant others (e.g., parents, teachers, caregivers) about the client’s preferences.

While these methods are often quick and easy to implement, they are generally considered less reliable than stimulus-based (direct) assessments.

This is because verbal reports may not always align with actual choices when items are physically present.

• Asking the Target Individual:
  • Open-ended questions: “What do you want to work for today?” “What are some of your favorite toys or snacks?” “What’s your favorite thing to do after school?”
  • Choice format: “Would you rather play with cars or blocks right now?” “Do you want a cookie or a cracker for your snack?”
  • Rank ordering: Presenting a list of potential preferred items or activities and asking the individual to rank them from most to least preferred.
• Asking Significant Others: Caregivers, parents, or teachers who know the individual well are asked about the individual’s preferences.
  This can be particularly helpful for individuals with limited communication skills.
• Surveys/Questionnaires: Formal checklists or questionnaires (e.g., the Reinforcer Assessment for Individuals with Severe Disabilities – RAISD) can be completed by caregivers or staff to gather information on a wide range of potential preferences.
• RBT Role in Ask-Based Methods: The RBT might be asked by their supervisor to administer these questions or questionnaires exactly as written and to record the responses verbatim, without adding their own interpretations.
• Limitations of Ask-Based Methods: Verbal reports can sometimes be unreliable due to factors like limited verbal skills, a desire to please the asker, difficulty choosing between abstract options without seeing them, or a discrepancy between what someone says they like and what they actually choose when the items are physically available.

Free Operant Observation (Naturalistic Observation)

In this direct observation method, the individual is observed in an environment where they have unrestricted access to a variety of potentially preferred items and activities for a set period.

The RBT simply observes and records which items or activities the individual engages with and, crucially, for how long they engage with each one.

There are no items presented or taken away by the RBT during the observation period itself; the RBT is a passive observer and data collector.

• Procedure:
  • The supervisor will typically identify a range of items and activities to make available in the observation setting.
  • The RBT ensures these items are easily accessible to the client within the environment.
  • The RBT observes the client for a predetermined amount of time (e.g., 10-30 minutes).
  • The RBT meticulously records the duration of engagement with each item or activity.
• Data Interpretation: Items or activities that the client engages with for the longest durations are considered highly preferred.
• Advantages: This method is less intrusive than trial-based methods. It’s particularly good for individuals who may have difficulty making choices when directly prompted or who might attempt to take all items if presented in an array.
  It can also help identify preferences for activities that are hard to present in other formats (e.g., looking out the window, rocking in a chair, listening to music).
• Types of Free Operant Observation:
  • Contrived Free Operant: The RBT or supervisor might pre-arrange specific items in the environment to specifically assess preference for those particular items.
  • Naturalistic Free Operant: The RBT observes the client in their everyday environment (e.g., playroom, classroom during free time) without adding or specifically arranging items beyond what’s typically available.

Trial-Based Methods (Stimulus Preference Assessments – SPAs)

These direct assessment methods involve systematically presenting stimuli (items or representations of activities) to the individual and recording their choices.

They are generally considered more accurate and reliable than ask-based methods for identifying a hierarchy of preferences.

• (a) Single Stimulus Preference Assessment (also known as “Successive Choice” or “Single Item Presentation”):
  • Procedure: One item is presented at a time to the individual.
    The RBT records whether the client approaches or interacts with the item, the duration of that interaction, or other pre-defined behavioral indicators of preference (e.g., positive vocalizations, attempts to reach for the item).
    Each item in the assessment set is presented multiple times, often in a random order to avoid predictability.
  • Data: Preference can be reported as the percentage of trials an item was approached or interacted with, or as the average duration of interaction across presentations.
  • When to Use: This method is particularly good for individuals who have difficulty making a choice when two or more items are presented simultaneously, or for those who may attempt to grab all items if presented in an array.
    It’s also useful for assessing preference for items that cannot be easily removed or presented in an array (e.g., a swing on the playground, a specific type of music).
  • RBT Role: Present one item clearly, observe for engagement (as defined by the supervisor e.g., client must touch the item, hold it for at least 3 seconds, or look at it and smile), accurately record the data, remove the item after a brief interaction period, and then present the next item in the sequence.
• (b) Paired Stimulus Preference Assessment (also known as “Forced Choice”):
  • Procedure: Two stimuli are presented simultaneously to the individual, and they are prompted to choose one (e.g., the RBT might say, “Pick one,” or “Which one do you want?”).
    Every stimulus in the assessment set is systematically paired with every other stimulus an equal number of times. The RBT meticulously records which item is chosen from each pair.
  • Data: Items are then ranked based on the percentage of trials in which they were chosen when available. This method provides a clear preference hierarchy.
  • When to Use: This method is effective for individuals who can make a clear choice between two items but might be overwhelmed by a larger array of choices.
    It can be more time-consuming than some other methods if many items are being assessed, due to the number of pairings required.
  • RBT Role: Present two items simultaneously (one in each hand, or side-by-side on a table), wait for the client to make a selection, allow brief access to the chosen item, accurately record the choice, remove both items, and then present the next pair according to a predetermined sequence (the supervisor will provide this sequence).
    It’s crucial to ensure that items are presented equally on the client’s left and right sides across trials to control for any potential side bias.
• (c) Multiple Stimulus Preference Assessment:
  These methods involve presenting an array of three or more stimuli simultaneously.
  • Multiple Stimulus With Replacement (MSW):
    • Procedure: An array of items (e.g., 3-7 items) is presented to the individual. The client chooses one item and is allowed brief access to it.
      That chosen item is then returned to the array for the next trial. The positions of the other items in the array may be rotated or changed to avoid position bias.
    • Data: Each time an item is chosen, it’s recorded. Items that are chosen more frequently are considered more preferred.
      This method can sometimes result in the same high-preference item being chosen repeatedly, which might limit the identification of other, less intensely preferred items.
    • When to Use: This method is useful when you want to see if a very strong preference emerges for one or two items, or for individuals who might become distressed if a chosen item is removed permanently from the array during the assessment.
  • Multiple Stimulus Without Replacement (MSWO):
    • Procedure: An array of items (e.g., 3-7 items) is presented. The individual chooses one item and is allowed brief access to it.
      That chosen item is then removed from the array for all subsequent trials within that particular assessment session.
      The RBT then presents the remaining items in the array until all items have been chosen or the client makes no more choices from the remaining items.
    • Data: The order in which items are selected creates a clear preference hierarchy. The first item chosen is typically considered the most preferred, the second item chosen is the next most preferred, and so on.
    • When to Use: MSWO is generally considered one of the most efficient and effective trial-based methods for generating a ranked hierarchy of preferences.
      It’s good for individuals who can scan an array of items and make clear choices. This is a very common method that RBTs are trained to implement.
    • RBT Role (MSWO Example):
      • The RBT arranges 5 pre-selected items in a line in front of the client.
      • The RBT says clearly, “Pick one.”
      • The client picks Item C. The RBT allows brief interaction with Item C (e.g., 15-30 seconds), then removes Item C from the array. The RBT records on their data sheet: “Item C – 1st choice.”
      • The RBT then rearranges the remaining 4 items (Items A, B, D, E) in a new order to avoid position effects.
      • The RBT again says, “Pick one.”
      • The client picks Item A. The RBT allows brief interaction, then removes Item A. The RBT records: “Item A – 2nd choice.”
      • This process continues until all items are selected or the client makes no further selections from the remaining items.

Real-World Examples (Beyond the Method Descriptions)

• Pre-Session Quick Check (using MSWO): Before starting a Discrete Trial Teaching (DTT) session, an RBT might quickly present 3-4 known edibles or small, preferred toys using an MSWO format.
  This helps determine what the client is most motivated by at that specific moment, allowing the RBT to select the most potent reinforcer for the upcoming work.
• Identifying New Potential Reinforcers (using Free Operant): A client seems bored with their usual reinforcers. The supervisor asks the RBT to conduct a 20-minute free operant observation in a room that has been newly stocked with a variety of sensory toys, art supplies, and simple games.
  The RBT’s role is to carefully and objectively record the duration of the client’s engagement with each new item, providing data to the BCBA about potential new interests.
• For a Non-Verbal Client with Motor Limitations (using Single Stimulus): A client has significant physical challenges that make pointing to or grasping items difficult. The RBT, under supervision, might present single items (e.g., a light-up toy, a vibrating massager, a piece of fabric with a preferred scent) one at a time.
  The RBT would then record if the client orients their body or gaze towards the item, smiles, makes positive vocalizations, or shows other subtle, pre-defined signs of preference (as specified by the supervisor) within a 10-second window after presentation.

Key Terms/Vocabulary (Specific to Preference Assessments)

• Preference: An individual’s subjective liking for, or selection of, one stimulus (item, activity, etc.) over others.
• Reinforcer: A stimulus that, when delivered contingently immediately following a behavior, increases the future probability of that behavior occurring again. (Preference assessments identify potential reinforcers; further assessment confirms if they function as actual reinforcers).
• Stimulus: Any object, event, or condition in the environment that can be perceived by an individual and can potentially affect their behavior.
• Array: The set of stimuli presented together at one time in a multiple stimulus preference assessment.
• Trial: A single presentation of stimuli (or a single opportunity to choose) in a trial-based preference assessment.
• Hierarchy (Preference Hierarchy): A ranked order of preferences, typically from most preferred to least preferred, derived from the results of a preference assessment.
• Satiation: A decrease in the effectiveness of a reinforcer (and often a decrease in preference for it) due to repeated exposure or consumption.
  (One reason preference assessments are done regularly is to identify varied reinforcers to combat satiation).
• Deprivation: An increase in the effectiveness of a reinforcer (and often an increase in preference for it) due to restricted access to that stimulus for a period.
  (While not directly manipulated during typical RBT-conducted preference assessments, understanding this concept helps RBTs recognize when an item might be particularly motivating).
• Approach Response: The client physically moving towards or making contact with a presented stimulus.
• Engagement: The client interacting with a stimulus in a way that is appropriate to its function (e.g., playing with a toy correctly, eating an edible, participating in an activity).

Considerations for RBTs Implementing Preference Assessments

• Follow Supervisor Instructions Exactly: Each preference assessment method has specific procedural steps. Adhering to these steps with fidelity is crucial for obtaining valid and reliable results.
• Minimize Distractions: Conduct assessments in a relatively quiet environment with minimal competing stimuli, unless the assessment is specifically designed for a more naturalistic setting (like some free operant observations).
• Allow Brief Access to Chosen Items: For many trial-based methods (like Paired Stimulus or MSWO), it’s important to allow the client brief access (e.g., 15-30 seconds, as specified by the supervisor) to the item they choose before moving to the next trial.
  This confirms their choice was reinforcing and helps maintain their participation in the assessment itself.
• Vary Item Positions: In paired and multiple stimulus arrays, always vary the position of items across trials to control for any potential side biases
  (e.g., a client who always tends to pick the item on their right, regardless of what it is).
• Data Collection Accuracy: Record choices immediately and accurately on the data sheet. Don’t rely on memory.
• Pace: Work at a pace that is comfortable for the client but also efficient enough to complete the assessment within a reasonable timeframe.
• Problem Behavior: Have a plan, provided by your supervisor, for how to respond if problem behavior occurs during the assessment
  (e.g., if the client tries to take all the items at once, or has a tantrum when a chosen item is removed after the brief access period).
• Ethics: Ensure any edibles used are appropriate for the client’s dietary needs and allergies, and are not used excessively. Always prioritize the client’s well-being and dignity.

Common Mistakes/Misunderstandings (Specific to RBTs Conducting Preference Assessments)

• Confusing Preference with Reinforcement: A common error is assuming that because an item is highly preferred, it will automatically function as a reinforcer for any and all behaviors.
  Its actual reinforcing capacity needs to be verified through its effect on behavior.
• Incorrect Implementation of Specific Procedures:
  • For MSWO: Forgetting to remove the chosen item from the array before the next trial.
  • For Paired Stimulus: Not pairing every item with every other item systematically, or showing a strong position bias in how items are presented (e.g., always putting the “new” item on the right).
  • For Single Stimulus: Not allowing enough time for the client to interact with the item, or defining “interaction” too vaguely or inconsistently.
  • For Free Operant: Interfering by prompting choices, talking to the client, or directing their attention, instead of just passively observing and recording.
• Allowing Too Long or Too Short Access to Chosen Items During Trial-Based Assessments: If access is too long, it can lead to satiation within the assessment itself, skewing the results.
  If access is too short, it might not be reinforcing enough for the client to continue participating in the assessment. The supervisor will provide guidance on the appropriate duration of access.
• Not Randomizing Item Positions in Arrays: This can lead to a false hierarchy based on a client’s side preference rather than a true preference for the items themselves.
• Influencing Choices (Unintentionally): The RBT might subtly cue the client towards certain items through their eye gaze, facial expressions, how they hold the items, or slight hesitations in their presentation.
  RBTs must strive for neutral presentation.
• Conducting Preference Assessments Infrequently: Preferences can and do change! What was highly preferred last month (or even yesterday) might not be today.
  Regular re-assessment of preferences is often needed, especially if motivation seems to be lagging.
• Using Only One Method for All Clients: Relying on a single type of preference assessment (e.g., only ever doing an “ask” method) might not give the full or most accurate picture, especially if that method isn’t well-suited to the client’s specific skills or needs.
  (The supervisor chooses the methods, but RBTs might provide feedback to the supervisor on how a client responded to a particular assessment format).

Conducting preference assessments accurately and systematically is a fundamental skill for RBTs. It directly impacts the quality and effectiveness of the interventions and teaching strategies that follow.

By understanding and precisely implementing these procedures as directed, RBTs provide invaluable information to their supervisors, which helps in creating more engaging and effective ABA programs.

This detailed exploration of B-01 should give you a very comprehensive understanding of the RBT’s crucial role in conducting various types of preference assessments.

Next in Section B is B-02: Assist with Individualized Assessment Procedures (e.g., curriculum-based, developmental, social skills). This task expands on the RBT’s supportive role in different kinds of assessments.