03 · What You Need to Know
Designing Research Materials That Participants Can Understand and Use
What Does Accessibility Mean for Research Materials?
Accessible research materials allow participants with different capabilities and communication needs to obtain information, understand instructions, and complete relevant research activities without unnecessary barriers.
Accessibility may involve visual presentation, language complexity, compatibility with assistive technology, alternative communication methods, physical interaction requirements, or the cognitive demands of navigating a procedure.
For example, a questionnaire may use sufficiently large text but remain inaccessible because its response options cannot be selected using a keyboard. Another questionnaire may be technically compatible with a screen reader while containing questions so complex that some participants cannot interpret them reliably.
Accessibility therefore involves more than visual appearance or compliance with a single technical checklist.
Researchers should consider whether participants can perceive the material, understand its meaning, operate the required interface, and complete the intended task.
How Are Literacy Needs Different From Disability-Related Accessibility Needs?
Literacy concerns the ability to obtain, understand, evaluate, and use written or other forms of information within a particular context. Disability-related accessibility needs may involve sensory, physical, cognitive, communication, or other functional differences.
These categories can overlap, but they should not be treated as equivalent. A participant with limited reading proficiency does not necessarily have a disability. A participant with a visual impairment may have advanced literacy skills while requiring screen-reader-compatible materials.
Literacy accessibility
Ensuring that wording, structure, instructions, and information demands are understandable to the intended audience.
Disability accessibility
Removing barriers associated with sensory, physical, cognitive, communication, or other functional needs.
Usability
Ensuring that participants can navigate materials and complete tasks effectively within the intended research context.
Researchers should avoid inferring accessibility needs solely from age, diagnosis, educational attainment, or disability status. Direct consultation and appropriate user testing provide a more defensible basis for design decisions.
Which Research Materials Should Be Reviewed for Accessibility?
Accessibility review should cover the complete participation process. Making the questionnaire accessible is insufficient if the recruitment invitation or consent procedure remains inaccessible.
| Research material |
Potential barrier |
Possible improvement |
| Recruitment announcements |
Complex wording, inaccessible images, or limited distribution formats |
Clear invitations, accessible text alternatives, and suitable communication channels |
| Participant information sheets |
Dense paragraphs, unexplained terminology, or confusing organization |
Plain language, descriptive headings, and clearly presented key information |
| Consent forms |
Inaccessible document structure or difficult legal and technical language |
Accessible formats, understandable explanations, and supported consent discussions |
| Questionnaires |
Ambiguous questions, inaccessible controls, or complex response formats |
Accessible interfaces and appropriately evaluated item wording |
| Interview materials |
Communication methods unsuitable for some participants |
Approved interpretation, communication support, or alternative administration |
| Digital platforms |
Keyboard barriers, missing labels, or incompatible assistive technology |
Accessibility testing and remediation against relevant technical standards |
| Audio and video materials |
Missing captions, transcripts, or descriptions of essential visual information |
Accurate captions, transcripts, and appropriate audio description |
| Follow-up instructions |
Complicated schedules or information requiring extensive memory |
Clear reminders, manageable steps, and accessible communication options |
The appropriate improvements depend on the material's purpose. A consent document requires meaningful comprehension, while a standardized questionnaire also requires careful protection of measurement properties.
How Can Plain Language Improve Research Accessibility?
Plain language communicates information using familiar words, clear sentence structures, logical organization, and explanations suited to the intended audience.
It does not require removing scientifically necessary information or treating participants as incapable of understanding complex concepts. Instead, researchers should explain complexity without introducing avoidable linguistic obstacles.
For example, a consent form stating that participants will undergo a noninvasive assessment of cardiovascular parameters may be more understandable when it explains what measurements will be taken, how they will be collected, and what participants will experience.
The United States Centers for Disease Control and Prevention developed the Clear Communication Index to help evaluate communication materials. Its framework considers factors such as the main message, language, information design, numerical information, and communication of risk.
Researchers can adapt these principles to participant-facing materials while recognizing that the Index was developed for public communication and does not independently establish the adequacy of research consent or the validity of an instrument.
Technical terms should be explained when they are necessary. Important qualifications, risks, and uncertainty should not disappear merely to shorten the text.
Should Research Materials Meet a Particular Reading Grade Level?
Readability formulas can provide limited information about sentence length and word complexity, but they do not measure comprehension directly.
A document may receive a favorable readability score while remaining confusing because of unfamiliar concepts, ambiguous instructions, or poor organization.
Conversely, some technical terms may be familiar to the intended population even when a readability formula classifies them as difficult.
Researchers should therefore avoid treating a single reading grade level as universal proof of accessibility. Institutional policies or study-specific standards may prescribe particular targets, but those requirements should be interpreted alongside audience testing.
Comprehension testing with members of the intended population is generally more informative than relying on a readability score alone.
How Should Documents Be Structured for Screen Readers?
Screen readers rely on accessible document structure and underlying text to communicate content. A document that appears visually organized may not convey the same structure to someone using assistive technology.
Researchers should use genuine headings rather than merely enlarging or bolding text, preserve a logical reading order, and provide meaningful descriptions for informative images.
Tables should be used for actual tabular information, with properly identified headers and a structure that can be navigated meaningfully.
Scanned images of text can create accessibility barriers when they lack an accessible text layer. Converting a document to PDF does not automatically make it accessible.
For electronic documents, accessibility should be checked in the authoring format and again after export. Automated checkers can identify some issues, but manual inspection and assistive-technology testing remain important.
What Makes an Online Questionnaire Accessible?
Accessible online questionnaires should allow participants to understand questions, identify response options, navigate controls, correct errors, and submit responses using supported interaction methods.
The World Wide Web Consortium's Web Content Accessibility Guidelines (WCAG) 2.2 provide a technical framework for accessible web content. They address requirements relevant to perception, operation, understanding, and compatibility with assistive technologies.
For research questionnaires, relevant considerations include programmatically associated form labels, keyboard accessibility, visible focus indicators, sufficient contrast, understandable error messages, and appropriate instructions.
Researchers should also examine whether the questionnaire remains usable when text is enlarged or viewed on a smaller screen.
Accessibility cannot be established solely by selecting a survey platform that advertises compliance. Custom question types, embedded media, institutional authentication, and particular configuration choices may introduce barriers.
Where internet access requirements create additional exclusion, accessible digital design may need to be supplemented by alternative participation modes.
How Can Researchers Accommodate Participants With Visual or Hearing Disabilities?
Participants with visual disabilities may benefit from accessible electronic text, screen-reader compatibility, magnification, appropriate contrast, or alternative formats. The relevant accommodation depends on the individual's preferences and functional needs.
Participants with hearing disabilities may require accurate captions, transcripts, sign-language interpretation, or other communication arrangements.
Researchers should not assume that captions and sign-language interpretation are interchangeable. Sign languages have their own linguistic structures, and participants may differ in their preferred communication methods.
Audio descriptions may be necessary when essential information is conveyed visually in a video. Similarly, transcripts should communicate meaningful audio information rather than merely reproduce selected spoken words.
Where an assessment depends on hearing or vision, researchers must distinguish accommodations that provide access from changes that would alter the construct being measured.
How Can Research Materials Support Participants With Cognitive or Learning Disabilities?
Cognitive accessibility concerns how people understand information, maintain attention, remember instructions, and navigate tasks. Needs vary substantially across individuals and contexts.
The World Wide Web Consortium's guidance on making content usable for people with cognitive and learning disabilities recommends clear structures, familiar controls, understandable language, reduced unnecessary complexity, and opportunities for user testing.
For research materials, practical adaptations may include presenting one instruction at a time, separating complex procedures into manageable stages, providing clear examples, and allowing participants to review information without relying entirely on memory.
Additional time or communication support may also be appropriate, depending on the task.
Researchers should avoid assuming that a cognitive or learning disability automatically prevents informed consent. Decision-making capacity is specific to the decision and circumstances, and accessibility accommodations may support understanding.
Where a participant lacks the capacity required for a particular consent decision, applicable ethical and legal safeguards must be followed. Accessibility measures do not replace those requirements.
How Should Participants With Motor or Physical Disabilities Be Accommodated?
Physical accessibility may involve the ability to operate a device, select responses, sign documents, or interact with equipment.
Some participants may use keyboard navigation, voice input, switches, alternative pointing devices, or assistance with physical tasks.
Research platforms should not unnecessarily require precise mouse movements, prolonged button presses, or other interactions that some eligible participants cannot perform.
For in-person research, accessible venues, appropriate seating, reachable equipment, and sufficient time may also be necessary.
The accommodation should be evaluated in relation to the research task. Assistance with selecting a questionnaire response may be appropriate when the participant independently determines the answer, but it may be inappropriate when unaided physical performance is the construct under investigation.
Can Participants Use Assistance Without Compromising Research Integrity?
Assistance can support participation, but its implications depend on what the research is measuring.
For example, a participant may dictate responses to a trained researcher when the study concerns attitudes or experiences rather than independent writing ability. However, interviewer involvement may influence responses to sensitive questions.
In a study measuring independent reading comprehension, reading the assessment passages aloud may change the construct being assessed.
Researchers should distinguish access accommodations from modifications that alter the measurement itself.
| Accommodation |
Potential benefit |
Measurement consideration |
| Screen-reader access |
Enables nonvisual interaction with written materials |
May be appropriate for attitude surveys but not every visual-perception task |
| Interviewer-administered questionnaire |
Supports participants who cannot independently use the original format |
May introduce interviewer or social-desirability effects |
| Extended completion time |
Reduces time-related barriers |
May alter interpretation when response speed is part of the construct |
| Alternative communication device |
Allows participants to express responses using their preferred method |
Requires assessment of response accuracy and administration consistency |
| Simplified instructions |
Improves understanding of procedures |
Should preserve all essential information and task requirements |
Appropriate accommodations should be planned and documented rather than introduced inconsistently without considering their effects.
How Do Accessibility Changes Affect Standardized Research Instruments?
Standardized instruments are designed to support particular score interpretations under specified administration conditions. Changes to wording, response options, presentation, timing, or assistance may affect those interpretations.
Not every accessibility adjustment has the same implications. Enlarging text may leave the measured construct unchanged, while replacing a visual reasoning task with a spoken description may substantially alter what is being assessed.
Researchers should review instrument manuals, available validation evidence, and licensing conditions before modifying established measures.
When changes are necessary, appropriate evaluation may include expert review, cognitive interviewing, pilot testing, or psychometric analysis, depending on the research purpose.
Where different versions are administered, researchers should consider whether scores can be compared or combined.
This is an important example of the trade-off between accessible participation and measurement quality. The objective is not to preserve a barrier merely because it appears in the original procedure, but to ensure that accommodations support valid conclusions.
How Should Accessible Informed Consent Be Designed?
Accessible informed consent should communicate the research purpose, procedures, risks, potential benefits, voluntariness, and other required information in a manner the participant can understand and use.
Under the United States Common Rule, 45 CFR 46.116 requires consent information to be understandable and organized to facilitate comprehension. The Office for Human Research Protections also emphasizes that informed consent is an ongoing communication process rather than merely obtaining a signature.
Researchers may use accessible electronic documents, oral explanations, approved alternative formats, or communication support when appropriate.
However, a shorter or simplified form must not omit required information without an applicable and properly approved consent alteration or waiver.
Researchers should give participants adequate time to consider participation and ask questions. Checking understanding through appropriately designed discussion or comprehension questions may be useful, particularly for complex studies.
Any required consent documentation must follow the applicable legal, institutional, and ethics procedures.
How Can Researchers Test Whether Materials Are Actually Accessible?
Accessibility evaluation should combine technical review with testing involving people whose needs are relevant to the intended population.
Automated accessibility checkers can identify some problems, including missing labels, structural errors, or certain contrast issues. They cannot determine whether every question is understandable, whether an accommodation preserves the measured construct, or whether participants can complete a complex procedure independently.
Researchers should therefore conduct task-based testing. Ask participants to locate information, explain instructions in their own words, navigate questionnaire items, and complete representative activities using their usual assistive technologies where appropriate.
Testing should be respectful and voluntary. Participants should not be required to disclose unnecessary medical information merely to demonstrate an accessibility problem.
Findings should be documented, materials revised, and important changes retested.
The W3C's cognitive accessibility guidance specifically emphasizes involving people with relevant disabilities in design and usability testing rather than relying exclusively on assumptions made by developers or researchers.
Should Researchers Offer Multiple Accessible Formats?
Multiple formats can help address different needs, but the appropriate selection depends on the research population and procedures.
Options may include accessible digital text, large-print documents, audio materials, captioned video, interpreted communication, or approved assisted administration.
Providing alternatives should not require participants to disclose more personal information than necessary. Researchers can ask what format or assistance would enable participation rather than requiring detailed diagnostic explanations.
Alternative formats may also introduce practical costs and measurement considerations. The research team should determine which accommodations can be provided consistently and which require additional evaluation.
Where access needs involve different languages, linguistic accessibility and language-related exclusion should be considered alongside disability and literacy requirements.
Can Accessible Materials Improve Scientific Validity?
Accessible materials may improve the opportunity for relevant participants to contribute evidence and reduce errors caused by misunderstood instructions or unusable interfaces.
They may also support more complete data collection by reducing avoidable frustration, incomplete responses, and withdrawal associated with inaccessible procedures.
However, accessibility does not automatically eliminate selection bias or establish measurement validity. A technically accessible questionnaire may still use an inadequate sampling strategy or contain poorly constructed items.
Researchers should therefore examine the relationship between inclusive design and scientific validity in the context of the intended inference.
Accessibility is most valuable when it enables participation without introducing uncontrolled changes to the evidence being collected.
Watch Out
Do not assume that automated accessibility scores, readability formulas, or a platform's compliance statement prove that research materials are usable by every participant. Technical standards are important, but participant testing and study-specific evaluation remain necessary. Material changes to approved research procedures may also require ethics review.
