Guidance: Readability and Comprehension Standards

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Researchers are tasked with ensuring participants understand the purpose, benefits, risks, and voluntary nature of participating in research. In educational research settings, this information tends to be shared directly with potential subjects and their families via written documentation. These documents, often written as recruitment, consent, opt-out, and informational materials, present highly complex information.

The Belmont Report, which sets out basic ethical principles governing research involving human subjects, makes the following points about the informed consent process:

  • "The reasonable volunteer" standard: the extent and nature of information should be such that persons, knowing that the procedure is neither necessary for their care or education nor perhaps fully understood, can decide whether they wish to participate in the furthering of knowledge. Even when some direct benefit to them is anticipated, the subjects should clearly understand the range of risk and the voluntary nature of participation. 

  • The manner and context in which information is conveyed is as important as the information itself.
  • Because the subject's ability to understand is a function of intelligence, rationality, maturity and language, it is necessary to adapt the presentation of the information to the subject's capacities.

The Office of Research Integrity has instituted minimum standards and requirements to support the readability and comprehension of consent, opt-out, and information materials as described below.

Readability Standards

Readability should be guided by the following standards:

  • Materials should be written in a manner that is both understandable and sensitive to the target participant population(s).
  • It is not the participant’s responsibility to try to understand the study documents.
  • Refer to your partner organization’s or project site’s readability policies and practices.
  • When working with populations whose primary language is not English or who do not understand English, we recommend translating materials into their native language at the appropriate reading level. For additional guidance and IRB requirements, please visit International Research and Research With Non-English Speaking Populations.

Readability Requirements

Readability requirements include:

1. Appropriate Reading Level

Write to the literacy level of your intended population, with a maximum reading level at 8th grade. Assent materials for minors should be written to the child’s grade level but no higher than a 6th grade level.

  • Use the Flesch–Kincaid and/or Fry scoring methods (embedded in Microsoft Word) to estimate reading level.
  • If your population includes a range of ages or literacy levels, write to the lowest level.

2. Clearly Written Materials

Tips to write clearly and directly include:

  • Simplify, so long as it doesn’t affect the information shared. This includes the study title.
  • Write short, direct sentences. Divide sentences into two when necessary.
  • Make your text logically sequenced and clear to understand.
  • Keep paragraphs short and limited to one idea.
  • Use active voice instead of passive. Write the information and consent materials the way that you would naturally speak.
  • Keep words to three syllables or fewer. One-to-two syllable words are ideal.
  • Spell out acronyms when first used.
  • Use layman’s terms and everyday language whenever possible. Use words familiar to the non-technical or non-scientific reader.


  • randomization = toss of a coin
  • administer = give
  • determine = find out
  • in conjunction with = at the same time
  • participate = take part, be in
  • measure impact or evaluate or assess = learn about
  • instruments = surveys and tests
  • cognitive skills = thinking skills
  • virtual = online
  • discontinue = stop
  • investigation = study
  • utilize = use
  • assessment = test

3. Visual Ease

Make your materials visually appealing and easy to navigate.

  • Use adequate spacing and white space to make the content inviting to read. Avoid crowding of words and letters.
  • Use headings/subtitles. These reduce content density and serve as “road signs.”
  • Use lists rather than paragraphs when possible.
  • Use an acccessible, easy-to-read font (ex: Arial, Courier, Verdana). Avoid the use of unusual fonts. 
  • Use page numbers.
  • Use at least 12-point font and consider a larger font based on your audience.
  • Avoid excessive use of bold type, which can lead to subjects overlooking important information not in bold type.
  • Use photos, graphics or tables if these will help clarify procedures.

4. Supporting Comprehension and Further Clarifications

Provide opportunities for subjects to ask questions and clarify what they have read or been told. This could be in-person or supported by phone or email.

This guidance was adapted with permisson from the WestEd document "Regulated Research: Minimum Standards and Requirements - Readability & Comprehension of Informational Materials for Participants"