“What if Intellectual Disability is not what we believe it to be?”

Fotografía de Marcela Tenorio sonriendo.
Our alternate director at MICARE, Dr. Marcela Tenorio, wrote this column on intellectual disability for the Contrabajo Foundation’s blog, “Cultura Inclusiva” (Inclusive Culture).

By Marcela Tenorio. Read the column published by ConTrabajo Foundation, here.

What is intellectual disability?

The American Association for Intellectual Disability and Other Developmental Disorders (AAIDD) was founded in 1876 and it is the oldest intellectual disability group in the world. Since its creation, it has continuously studied the best ways to define and classify what is currently known as intellectual disability.

In 1910, the AAIDD first published a manual that defined for the scientific community what was then called “mental retardation”. Twelve versions of this document have existed to date, continuously updating our knowledge and understanding of this reality. Each edition includes ideas that bring new transformations and demands for academics, professionals, legislators, families, people with the condition themselves, and for all those with an interest in the area.

While I was writing this article, my mother, a 78-year-old littérateur and poet, wrote me a message saying:


Is there such a thing as emotionally disabled? Is this what we mortals know as mental retardation? Explain it to me, but just a little bit, not too much.

Well, I have spent a week trying to find a way to explain to her that no, there is no such thing as emotional disability, that we no longer talk about mental retardation and that we now refer to intellectual disability.

Plus, trying to make my explanation “just a little bit, not too much”.

I’ve gone back and forth to arrive at this answer, so I’d love for my mom, and all of my readers, to walk away with three ideas:

Foto que muestra una pila de papeles de colores donde el primero tiene dibujado un signo de interrogación.
1. The definition of intellectual disability

The definition of intellectual disability that is used today is more than 60 years old, clear, and concise.

We speak of intellectual disability when three criteria coexist simultaneously:

  • There is a significant limitation in intellectual functioning.
  • There is a significant limitation in adaptive behavior.
  • It is a neurodevelopmental condition.

No more, no less.

Of course, my mom would immediately ask me: “What was that you said?” I’m aware that most people don’t know the operational definitions of the three criteria. So, for the sake of clarity:

(1 ) The term intellectual functioning incorporates: (a) the common definition of intelligence, (b) the skills that are assessed with intelligence tests (learning skills, reasoning, problem-solving, etc.) and (c) the consensus that intellectual abilities are influenced by other dimensions of human functioning and by support systems. That is, intellectual functioning is not IQ, but we accept that this is a valid measurement to be used as a guide or approximation.

(2) The term adaptive behaviour refers to the collection of acquired conceptual, social, and practical skills that a person exercises in daily life.

  • Conceptual skills include language and literacy acquisition, the concept of money, time, and numbers in general, among others.
  • Social skills consider interpersonal skills, mastering social norms, and self-esteem, among others.
  • Practical skills, on the other hand, include daily living activities, self-care, occupational skills, money management, telephone and other technologies management, transportation and navigation management, schedules and routines, and so on.

‘not all people with disabilities have the same performance profile, but these variables together make it possible to identify the condition’.

Marcela Tenorio, MICARE alternate director.

(3) And finally, the idea that it is a neurodevelopmental condition refers to the fact that intellectual disability is present since childhood, and that it is possible to identify it retrospectively with an onset before the age of 22.

We speak of intellectual disability when three criteria coexist simultaneously: There is a significant limitation in intellectual functioning. There is a significant limitation in adaptive behavior. It is a neurodevelopmental condition.
Classification of intellectual disability in Chile and the world

While it is somewhat more technical, I would like to clarify that we no longer use the parameter of “two standard deviations” below the mean (i.e., an IQ below 70) to classify disability. Instead, psychologists consider the error band from the confidence interval—although these details are more relevant to assessment professionals.

I would explain, however, that in Chile, the only two tests that meet the standard for measuring intellectual functioning are the WISC-V and the WAIS-IV, and for adaptive behaviour, the ABAS-2.

Until we have other advanced test developers, we will not be able to improve our tools.

2. The latest changes

For those interested, let’s take it a step further: the most recent AAIDD Handbook was published in March 2021 (Schalock, Luckasson & Tassé), is brand new, and comes with a twist.

In my opinion, there are three proposals in the latest edition that are frankly transformative.

The first is that we must be able to work from an integrative approach that allows us to understand that there are four possible approaches to intellectual disability and each of them has something to contribute (biomedical, psychoeducational, social, and rights-based approach).

The second invites us to incorporate three steps when working with people with disabilities:

  • Diagnosis
  • Classification
  • Design of support systems.

This seems like the bare minimum, but in reality, it often did not and does not occur. Work with the community should always consider these stages.

The third is that there is a frank operationalization of clinical judgment, meaning that it is no longer “experience”, “feeling” or anything similar, but rather precise and well-defined actions that establish the scope of what we professionals can ethically do. This is especially important because although we often have instruments that meet the international standard, other times this is not possible.

Fotografía de una mujer con discapacidad intelectual trabajando en una panadería.
In Chile, we need a profound reform of the regulations that govern the spaces of education, work, legal capacity, and cognitive accessibility at all levels of the public sector.
3. Consequences of this definition

The changes in the AAIDD manuals are necessary transformations to incorporate new knowledge into our work; but, above all, they are an essential space for us to achieve a comprehensive and interdisciplinary approach in which the person with a disability, in their full will, is placed at the centre of our actions.

We must call for our system of public policies, regulations, norms, and our institutional framework to be aligned on the minimum necessary to guarantee quality services and spaces for the full expression of the will of persons with intellectual disabilities.

Intellectual Disability is a complex condition that requires territorial and community actions, as well as transformations at the national level so that we can move towards a respectful exercise of rights..

In Chile there are countless tasks pending with the collective

These include a profound reform of the regulations governing the fields of education, work, legal capacity, and the inclusion of cognitive accessibility at all levels of the public sector.

We must ensure that forced sterilization is left behind as soon as possible and move decisively to rethink the regulation of employment policies.

Contemporary definitions set the minimum threshold for our work, and we need to realize that they are evolving.

While the most developed countries are advancing and aligning themselves with these changes, achieving dynamic laws that keep pace with scientific progress, we still have obsolete pieces of legislation that only serve to further harm the most vulnerable groups in our society.

To take care of each other is also to update ourselves: to know that being “ethical” is not enough, because ethics are depleted when they don’t go hand in hand with knowledge.