Defining and applying a functionality approach to intellectual disability.
A 2013 call to merge skills, supports, and outcomes became the 2021 AAIDD manual you can use Monday morning.
01Research in Context
What this study did
McGeown et al. (2013) wrote a think-piece, not an experiment.
They asked: how can we glue together three parts of ID services—what a person can do, what help they get, and what results they reach?
Their answer was a new "functionality approach" that links these parts in one picture.
What they found
The paper does not give numbers.
It gives a map: list the person’s skills, list the supports, then track real-life outcomes like having friends or a job.
The authors say this one-page map could replace the old split between IQ scores and support plans.
How this fits with other research
Hamama et al. (2021) later built the same idea into the AAIDD manual.
They added a tested scale that tells you exactly how much support a client needs—turning the 2013 dream into a tool you can score.
Brown et al. (2013) published the same year with a similar plea but used the Capabilities Framework instead; the two papers agree on individual focus, they just use different names.
Jones et al. (2010) came earlier and mapped policy principles onto the same ecology model; R et al. folded that policy layer into their bigger frame.
Why it matters
You no longer have to pick between measuring skills, writing support plans, or tracking outcomes—AAIDD’s 2021 manual packages all three.
Try filling out the Support Intensity Scale for your next client, then link each support to a life goal you can count (bus rides taken, texts sent, shifts worked).
This keeps your treatment plan, your data sheet, and your funding justification on the same single page.
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02At a glance
03Original abstract
BACKGROUND: The current functional models of disability do not adequately incorporate significant changes of the last three decades in our understanding of human functioning, and how the human functioning construct can be applied to clinical functions, professional practices and outcomes evaluation. METHODS: The authors synthesise current literature on human functioning dimensions, systems of supports and approaches to outcomes evaluation for persons with intellectual disability (ID), and propose a functionality approach that encompasses a systems perspective towards understanding human functioning in ID. The approach includes human functioning dimensions, interactive systems of supports and human functioning outcomes. RESULTS: Based on this functionality approach the authors: (1) describe how such an approach can be applied to clinical functions related to defining ID, assessment, classification, supports planning and outcomes evaluation; and (2) discuss the impact of a functionality approach on professional practices in the field of ID. CONCLUSIONS: A functionality approach can increase focus on the integrative nature of human functioning, provide unified language, align clinical functions and encourage evidence-based practices. The approach incorporates a holistic view of human beings and their lives, and can positively affect supports provision and evaluation.
Journal of intellectual disability research : JIDR, 2013 · doi:10.1111/j.1365-2788.2012.01575.x