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Nearly 60 million patients in the United States live with disabilities.1 Although patients with disabilities show high engagement with health care services and represent about one-quarter of health care expenditures in the U.S.,2 this large group remains underrepresented in clinical research trials. As a result, any treatments or therapies developed from these trials may not be generalizable to people with disabilities—who may need them the most.

In many cases, people with disabilities are explicitly excluded from clinical trials, usually with poor justification. For example, some research studies exclude people with disabilities for fear that “the effect of the intervention would be difficult to determine” due to disability or that the results of the study would be confounded by the presence of comorbid conditions.3 Other justifications include cost and resource constraints associated with providing accommodations for people with disabilities, even though analysis finds that as many as half of people with disabilities who are excluded would be able to participate without any accommodations.4

Trial design and recruitment strategies may also implicitly exclude people with disabilities. Among other accessibility barriers, people with disabilities may have limited access to transportation to and from medical research centers; they may be unable to access or read recruitment and consent forms; and they may be unable to complete study instruments as they are administered without accommodation (for example, a visually impaired person who cannot complete a written questionnaire unassisted or unaccommodated).5 Again, investigators’ resistance to inclusively adapting research design remains a major barrier to representation among people with disabilities.

Taken together, the explicit and implicit biases present in most clinical trials exclude people with disabilities by design. Disability advocates have recognized the urgent need to overcome barriers to fair representation in health research, and they have worked to develop and disseminate recommendations for improving equitable and accessible recruitment, retention, and participation in clinical trials.

In recent years, disability advocates have recommended that clinical trial researchers implement an approach known as Universal Design of Research (UDR). In contrast with some other disability models, which aim to accommodate individual needs within a fundamentally inaccessible environment, the UDR framework promotes broader inclusion by constructing an entirely new research architecture with a focus on maximum accessibility by a wide spectrum of participants. Optimally, a clinical trial designed with the UDR approach would:6

  • Remove disabilities from eligibility exclusion criteria
  • Confer with disability experts to optimize accessibility
  • Use multiple modalities (e.g., visual, verbal, written, etc.) to reach and recruit participants with diverse needs
  • Provide multiple methods for communicating study instructions and instruments to accommodate people with various needs (e.g., providing materials in Braille or communicating verbally for people with visual impairment)
  • Provide multiple methods for participants to complete study instruments (e.g., provide a sign language interpreter during conversational self-report interviews).

Given the wide availability of assistive devices and accommodation strategies, no clinical trial should exclude people with disabilities on the basis of barriers to accessibility. Researchers must seek to deliberately design research studies with a focus on equitable access for all participants, regardless of disability status; draft recommendations released by the Food and Drug Administration in 2019 may provide useful, practical guidance towards this goal.7 Fair inclusion and representation in clinical trials is a critical step towards improving health outcomes and quality of life among the millions of Americans who live with disabilities.


1 Banas JR, Magasi S, The K,  & Victorson DE. (2019). Recruiting and retaining people with disabilities for qualitative health research: Challenges and solutions. Qualitative Health Research, 29(7):1056-1064. 

2 Anderson WL, Armour BS, Finkelstein EA, & Wiener JM. (2010). Estimates of state-level health-care expenditures associated with disability. Public Health Reports, 125(1):44-51. 

3 Rios D, Magasi S, Novak C, & Harniss M. (2016). Conducting accessible research: Including people with disabilities in public health, epidemiological, and outcomes studies. American Journal of Public Health, 106(12):2137-2144. 

4 Feldman MA, Battin SM, Shaw OA, & Luckasson R. (2012). Inclusion of children with disabilities in mainstream child development research. Disability and Society, 28(7):997-1011.

5 Meyers AR & Andresen EM. (2000). Enabling our instruments: Accommodation, Universal Design, and access to participation in research. Archives of Physical Medicine and Rehabilitation, 81:S5-9. 

6 Williams AS & Moore SM. (2011). Universal Design of Research: Inclusion of persons with disabilities in mainstream biomedical studies. Science Translational Medicine, 3(82). 

7 Food and Drug Administration (FDA). Enhancing the Diversity of Clinical Trial Populations—Eligibility Criteria, Enrollment Practices, and Trial Designs: Guidance for Industry. (2019). Accessed from: https://www.fda.gov/media/127712/download