Where are persons with intellectual disabilities in medical research? A survey of published clinical trials.
Medical trials shut out people with ID even though tiny changes would let them in.
01Research in Context
What this study did
The authors read 300 recent high-impact medical trials. They counted how many welcomed people with intellectual disability. They also looked for rules that kept these adults out.
It was a simple survey, not an experiment. The goal was to see how wide the research gap really is.
What they found
Only six trials out of 300 clearly included people with ID. Most studies used wording that blocked them by default.
Yet seven in ten trials could have let them join with easy fixes like plain-language consent or caregiver travel help.
How this fits with other research
Tavassoli et al. (2012) said exclusion is an ethical problem. They argued a human-rights lens should guide study design. Laugeson et al. (2014) now gives the numbers that prove the problem is huge.
Heald et al. (2020) and Lotfizadeh et al. (2020) show the fallout. Adults with ID get fewer cancer checks and specialist visits. The chain is clear: no trials, then less care.
Pickard et al. (2022) flips the script. They gave adults with ID adapted health surveys and the group answered just fine. Simple tweaks work when we try them.
Why it matters
You write protocols, consent forms, or clinic policies. Add a line that welcomes adults with ID. Swap jargon for plain words, offer extra time, let a supporter come along. These micro-edits open science and, down the road, improve medical care for a group that is largely invisible.
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02At a glance
03Original abstract
BACKGROUND: Persons with intellectual disabilities (ID) are exposed to the same medical interventions as everyone else. Given the unique health profiles of many persons with ID, it cannot be assumed that they will react to medical treatments the same as persons without ID. It is not clear if medical clinical trials routinely include persons with ID. The purpose of this research survey was to examine the inclusion of persons with ID in medical research trials, and to determine whether accommodations and/or study modifications could have been made to promote greater inclusion in medical research. METHOD: Three hundred randomised control and clinical trials published between 2007 and 2011 in the six highest impact medical journals were randomly selected. Each study was reviewed for inclusion of persons with ID, and possible accommodations that could have been put in place without compromising research integrity. Corresponding authors received a follow-up survey to determine whether persons with ID were included, but were not mentioned in the article. RESULTS: Only 6 (2%) of 300 randomly chosen studies clearly included persons with ID. Over 90% of studies were designed in ways that would automatically exclude persons with ID from participating. The author survey revealed three additional studies including persons with ID. Most persons with ID could have participated in at least 70% of the studies with simple accommodations and/or minor procedural modifications. DISCUSSION: The findings highlight the exclusion of persons with ID in medical research. Efforts are needed to increase inclusion through research policy initiatives and education.
Journal of intellectual disability research : JIDR, 2014 · doi:10.1111/jir.12091