“The information that is given to the subject or the representative shall be in
language understandable to the subject or the representative.”
21 CFR 50.20, General Requirements for Informed Consent
Anyone involved in the informed consent process for a clinical study appreciates the challenge of explaining esoteric concepts in general terms. Testing drugs and devices in people involves complicated topics that we must explain successfully to any potential subject. The FDA’s recent draft guidance on informed consent–Informed Consent Information Sheet: Guidance for IRBs, Clinical Investigators, and Sponsors—shows us two aspects of this challenge: in one section it emphasizes the importance of readability in a consent form, but in the next it recommends consent form language that seems overly complicated.
According to the FDA, keeping consent forms “understandable” means that “the information presented to potential subjects is in a language and at a level the subjects can comprehend.”  Fair enough, but less than a page later the same guidance document presents the following as “one possible way” to explain research-related injuries:
In the event that you suffer a research-related injury, your medical expenses will be your responsibility or that of your third-party payer, although you are not precluded from seeking to collect compensation for injury related to malpractice, fault, or blame on the part of those involved in the research.
Does this sentence pass the FDA’s own test for ‘understandable’? One way to check is to measure its reading level, and Microsoft Word offers two quick ways to do so. After a few clicks to activate the feature, Spellchecking in Word reports on readability using two standards:
- Flesch Reading Ease – This gauge runs from zero to 100; the lower the score, the harder the document is to understand. Microsoft Word’s Help section recommends a Flesch Reading Ease score ranging between 60 and 70. (For reference, a draft of this blog without the FDA’s language scored 54.4)
- Flesch-Kincaid Grade Level – This test scores text according to the reading level for US school grades. For example, anything that an eighth grader should understand gets a score of 8.0. For general writing, Word’s Help section suggests scores between 7.0 and 8.0. (This blog—minus the FDA’s language—scored 9.3)
- Flesch Reading Ease: 10.3. The lower the score, the harder the section is to understand, so this is pretty close to the peak of complexity.
- Flesch-Kincaid Grade Level: 23.9. That is to say, the FDA’s 49-word sentence weighs in at a post-graduate level, maybe for the reading pleasure of law or medical school graduates.
These scores suggest another question: should consent forms have a “correct” reading level? People often cite the need to write consent forms at an eighth grade reading level. A 1998 article “Patient Literacy, a Barrier to Quality of Care”, supports that goal. The article’s authors found that U.S. adults “typically read three to five levels lower than the grade level they completed.” Assuming that drug study candidates have completed high school, then targeting an eighth grade reading level makes sense.
But we already have seen how difficult it can be to get the language right, especially considering the complex medical topics a consent form might include. The new FDA guidance does not set a required reading level; the heartiest endorsement the FDA can muster is a passive-voiced reference in a footnote:
A recommendation that consent forms be written at an eighth grade or lower reading level was made by the working group formed by the National Cancer Institute (NCI), along with the Office for Protection from Research Risks (now the Office of Human Research Protections, OHRP) and FDA in the 1998 “Recommendations for the Development of Informed Consent Documents for Cancer Clinical Trials” available at http://www.cancer.gov/clinicaltrials/conducting/simplification-of-informed-consent-docs/page2.” 
That footnote shows that others beside the FDA have concerned themselves with consent form readability. The National Institute of Health has created its own informed consent template for cancer trials, which seems to have done a better job of readability than the FDA. Check out the NIH’s language for research-related injuries, the same topic the FDA’s language addressed:
What happens if I am injured or hurt because I took part in this study?
If you are injured or hurt as a result of taking part in this study and need medical treatment, please tell your study doctor. The study sponsors (will/will not) offer to pay for medical treatment for injury.
Your insurance company may not be willing to pay for study-related injury. If you have no insurance, you would be responsible for any costs.
If you feel this injury was a result of medical error, you keep all your legal rights to receive payment for this even though you are in a study.
And here is how the NIH’s language scores on the two readability scales:
- Flesch Reading Ease: 61.3; just within the recommended 60 – 70 range.
- Flesch-Kincaid Grade Level: 9.1; not quite eighth grade, but 14 levels closer than the FDA.
So the NIH’s version shows that, while challenging, it is possible to improve a consent form’s readability.
Read more articles by Jim Gearhart.
Read other posts about the draft version of the FDA’s Informed Consent Information Sheet: Guidance for IRBs, Clinical Investigators, and Sponsors.