Skip to content

Preference Assessments


What motivates you? I know for myself any kind of hazelnut chocolate is a favourite. But what happens when I am sick of chocolate? I have my back up motivators – like sour candies, pretzels, cookies, and more! Not everyone can tell us what motivates them, and sometimes what we think will motivate us does not do the trick. This is why we have preference assessments.

What Is A Preference Assessment?

A preference assessment is a tool used to guide practitioners in providing reinforcement to a client to increase the future probability of a behaviour. Plainly, a preference assessment tells us what will motivate an individual at a specific point in time.

Why Use A Stimulus Preference Assessment?

When a client engages in an appropriate response, a reinforcer is provided contingent on their response. This is done to increase the future likelihood of a similarly appropriate response occurring in a similar situation. A preference assessment guides the practitioner in determining which stimuli will act as a reinforcer to increase future behaviour. Conducting a preference assessment will tell us under which conditions (such as tasks, states of deprivation, or reinforcement schedules) preferences are most valuable.

Use our Preference Assessment to help you in your pairing sessions!

The Three Types Of Stimulus Preference Assessments:

For all types of Stimulus Preference Assessments, be sure to present stimuli from various sensory systems (tactile, visual, auditory, etc.), and present them in randomized order.


You can ask the target individual, depending on their communication style and level, asking can be in the form of interviews and questionnaires, or visuals with pictures of the items/activities. Open-ended questions such as: “what toys do you like to play with during your free time?”; choice format where the individual picks between options such as “would you like chocolate or the race car?”; and rank ordering “list the following items from most preferred to least preferred: chocolate, race car, colouring”. These are all ways to ask about stimulus preferences.

Asking significant others is also an important resource to use. The same types of questions for the target individual can be adapted for the significant other to answer. Significant others can include parents, teachers, siblings, other close family members, or others.

Offering a pre-task choice, such as asking “what do you want to earn for doing this task?” is another form of asking about preferences.

Free-Operant Observation

Free-operant observation allows the target individual to have unrestricted access to various items and activities, and the practitioner observes and records. The individual is free to navigate the items. There are two types of free-operant observation used: contrived and naturalistic.

Contrived free-operant observation is where the practitioner sets up an environment with items of probable reinforcing value. These items can be determined through interviews and/or questionnaires with the target individual and significant others. When the target individual explores the items in the environment, the practitioner takes data on the total duration of time the individual engages with the item.

Naturalistic free operant observation occurs in the target individual’s natural environment, without the practitioner including additional stimuli. As with the contrived free-operant observation, the practitioner watches and records the learner’s behaviour and total duration with items.

The longer the duration with a particular item, the higher the preference value is given.

Trial-Based Methods

Where the free-operant observation entailed the learner taking the lead and exploring items naturally, the trial-based methods include a more active role on behalf of the practitioner. Here, stimuli are presented in trials, and data on responses are recorded.

The single stimulus method is when one item is presented at time. This style for preference assessment is perfect for the learner who has difficulty choosing between two or more stimuli. The reaction of the target individual is recorded, such as if they approached or moved away from the item, as well as data on total duration of engagement with the stimulus.

Paired stimuli, commonly referred to as forced choice, are presented two at a time to the target individual and their choice of one item over another is recorded. Individual stimuli are paired with every other stimulus in a set and presented randomly. Data is collected on how many times a single item is chosen.

The multiple stimuli method is similar to the paired stimuli method. However, instead of pairs of 2 stimuli are presented in an array of 3 or more. This is a quicker method as more stimuli are presented at a single time.

Multiple stimuli with replacement is where the item that is chosen stays in the array for the next set, and the unchosen items are replaced. Multiple stimuli without replacement is when the chosen item is removed from the set, and the following trial occurs with the remaining stimuli.

How To Run Preference Assessments?

Any preference assessment is a two-step process. It requires multiple stimuli that are potential reinforcers be compiled, and then those potential reinforcing stimuli need to be presented to the target individual using one of the abovementioned methods. And as always, data data data.

3 thoughts on “Preference Assessments”

  1. Pingback: ABA Pairing - How to ABA

  2. Pingback: Beginner Requesting - How to ABA

  3. Pingback: preference assessment data sheet - konkeng & konkeng

Leave a Reply

Your email address will not be published. Required fields are marked *

Captcha loading...