Stimulus Preference Assessment Decision-Making System (SPADS): A Decision-Making Model for Practitioners
Let SPADS pick your next preference assessment in under a minute by balancing client needs, item traits, time, and re-check schedule.
01Research in Context
What this study did
Lill et al. (2021) built a decision map for picking preference assessments. The map is called SPADS.
SPADS weighs four things: stimulus traits, client traits, time cost, and how well two tests agree.
What they found
The paper is a map, not an experiment. It tells you how to choose, not what one test does.
The goal is faster, better matches between kids and reinforcers.
How this fits with other research
Verriden et al. (2016) already showed paired-stimulus and MSWO give the steadiest ranks. SPADS folds that fact into its time-cost slot.
Curiel et al. (2020) gave us a free MSWO web tool. SPADS says when to click on it versus when to pick something else.
Bigwood et al. (2026) proved small tweaks make tests happier for adults with dementia. SPADS can point you to those tweaks when the client traits box says "dementia."
MacNaul et al. (2021) found preferences stay stable only if you re-test every 8-30 days with paired-stimulus. SPADS uses that window as its "expected agreement" guide.
Why it matters
You no longer have to guess which assessment to run. Walk through the four SPADS questions: How complex are the items? What can my client tolerate? How much time do I have? How often will I need to re-check? The map turns past research into a one-minute choice.
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02At a glance
03Original abstract
A stimulus preference assessment (SPA) is a fundamental tool used by practitioners to predict stimuli that function as reinforcers. The Behavior Analyst Certification Board (BACB) requires that all certified behavior analysts and behavioral technicians be trained in SPA methodology (BACB, 2017). SPA procedures are used by nearly 9 out of 10 behavior analysts in the field (Graff & Karsten, 2012). Over the last 4 decades, there has been a litany of research on SPA procedures. Despite the universality of training, application, and research, discussions on the selection of SPA procedures have been sparse. Two peer-reviewed articles have focused on clinical decision making in the selection of SPA procedures. Karsten et al. (2011) introduced an in situ decision-making model, whereas Virues-Ortega et al. (2014) developed an a priori algorithm based on client and stimuli characteristics. The SPADS addresses the limitations of prior models by considering the effects of stimuli dimensions, client characteristics, relative administration times, and the outcomes agreement between two potentially efficacious, context-specfic SPA procedures.
Behavior Analysis in Practice, 2021 · doi:10.1007/s40617-020-00539-3