Healthcare Readability: What FDA and HHS Rules Say
What US rules and FDA guidance actually say about the reading level of patient materials, where the 6th- and 8th-grade targets come from, and how to check your text.
US rules for patient materials ask for wording people can understand. They rarely name a number. The grade-level targets you hear about, 6th grade and 8th grade, come from guidance documents and from medical research, not from the regulations themselves.
This post sets out what the rules and FDA guidance say, where the targets come from, and how to check your own text. We read each source on 8 October 2026. This is a summary for writers, not legal advice. State rules, payer contracts and your own organisation's policy can add requirements that are not covered here.
What the regulations require
These rules are binding. None of them names a grade level or a readability formula.
| Document | Rule | What it requires |
|---|---|---|
| Medication Guides | 21 CFR 208.20 | "Nontechnical, understandable language" and type no smaller than 10 points |
| Informed consent (FDA-regulated research) | 21 CFR 50.20 | Information "in language understandable to the subject" |
| Informed consent (federally funded research) | 45 CFR 46.116 | Understandable language, and a "concise and focused presentation of the key information" at the start |
| Over-the-counter drug labeling | 21 CFR 330.10 | Terms "likely to be read and understood by the ordinary individual, including individuals of low comprehension" |
| Notice of privacy practices (HIPAA) | 45 CFR 164.520 | A notice "written in plain language" |
| Summary of Benefits and Coverage | 45 CFR 147.200 | "Terminology understandable by the average plan enrollee" and print no smaller than 12 points |
The pattern is the same in each one. The rule sets a standard, "understandable" or "plain," and leaves the measurement to you.
What FDA guidance suggests
FDA guidance documents do give numbers. Guidance is the agency's current thinking. It is a recommendation, and each document says it does not bind FDA or the public.
Consumer medication information. FDA's 2006 guidance, Useful Written Consumer Medication Information (CMI), says: "we suggest that CMI be provided at the sixth to eighth grade reading level." It names no formula.
Medical device patient labeling. FDA's 2001 Guidance on Medical Device Patient Labeling says that if the reading level is predicted to be above the eighth-grade level, the labeling should be rewritten.
The device guidance also warns about how to use formulas. It says they "should be used to predict (not measure) the reading level of the text," and that they "should not be used to write, rewrite, and revise" labeling to a specific level. Swapping easy words for hard ones, it notes, "does not necessarily make the text more readable."
Where the 6th- and 8th-grade targets come from
The two most quoted targets are attributed to medical bodies, not regulators.
A 2021 review in the Journal of Patient Experience puts it this way: the American Medical Association and the National Institutes of Health "recommend that patient materials be written at the sixth and eighth grade reading level, respectively."
That review scored 2,585 patient education materials from medical journals. Only 2.1% met the 6th-grade target, and 8.2% met the 8th-grade target. Most patient material is written well above either number.
We have not read the AMA's or NIH's own documents, so we describe these targets as "attributed to" them.
Which formula to use
No rule or guidance document we read requires a particular formula. The choice is yours, and research can guide it.
A 2013 review of readability formulas in health information concluded that SMOG "appears best suited for health care applications." It also found that formulas varied by up to five grade levels on the same text. That gap is the reason to state which formula you used whenever you report a grade.
A sensible approach:
- Use SMOG as your main score for patient materials. Our SMOG calculator explains how it works.
- Check it against other formulas. A wide gap between SMOG and Flesch-Kincaid usually means long medical words are the problem. Our guide to the formulas covers what each one measures.
- Record the formula and the score with the document, so a reviewer can repeat the check.
How to check your own material
- Find out which target applies. Ask your compliance team, review board or client. If nobody has set one, 6th to 8th grade is the range FDA's medication guidance suggests.
- Score the text. Paste it into a readability checker that shows several formulas. Text is scored in your browser, so drafts are not uploaded.
- Rewrite the long sentences first. Then replace medical terms with plain ones where the meaning stays exact. Our list of one-syllable substitutes for jargon can help.
- Keep accuracy. A lower grade is not a win if the instruction is now wrong. "Take one tablet every evening" must still say every evening.
- Test with real readers. FDA's device guidance makes the point that a formula predicts readability, and that a reader "must actually read the text to determine if it is readable."
For targets by audience, see what counts as a good readability score. For consent forms and discharge instructions, see our patient information guide.
What we did not find
An earlier version of this post made claims we could not support, and we have removed them. In the documents we read, we found:
- no FDA or CMS rule that sets a 6th-grade requirement,
- no rule that ties payment or audits to a readability score,
- no rule that names SMOG or Flesch-Kincaid as required.
If you know of a rule that does one of these things, tell us and we will add it with a link to the source.
How we checked
We read the current text of each regulation on eCFR, and the two FDA guidance documents, on 8 October 2026. Quoted wording is taken from those sources. Rules change, so check the current text before you rely on any of this for a compliance decision.
Frequently asked questions
What reading level does the FDA require for patient materials?
No FDA regulation sets a grade level. FDA guidance suggests a sixth to eighth grade reading level for consumer medication information, and says device patient labeling predicted above an eighth-grade level should be rewritten. Guidance is a recommendation, not a binding rule.
Does the FDA or CMS require SMOG or Flesch-Kincaid?
No. None of the FDA or HHS rules and guidance documents we checked names a required formula. Researchers who compared formulas on health materials found SMOG best suited to health care, so many health writers use it by choice.
Does HIPAA set a reading level for privacy notices?
No. The HIPAA Privacy Rule requires a notice of privacy practices that is written in plain language. It names no grade level and no formula.
What reading level should a consent form be?
FDA and HHS rules require consent information in language understandable to the subject. They set no grade. Institutions often set their own target, so check your review board's policy before you rely on a general number.