The Readability Gap No One Talks About

The numbers are stark.

Informed consent forms in clinical trials average a 10th to 14th grade reading level. The average American adult reads at a 7th to 8th grade level. Only 8% of consent forms meet the recommended readability threshold.

This isn't news to anyone who works in clinical research. We've known about the readability gap for decades. And yet, 35% of participants still cite difficulty understanding informed consent as a reason for dropping out.

Why does this persist?

Part of it is regulatory caution. Consent forms are legal documents, reviewed by IRBs, scrutinized by sponsors. The instinct is to add language, not remove it. To cover every contingency, every risk, every possibility.

The result is a document that protects the institution but fails the participant.

Comprehension isn't a one-time event.

Here's what we often miss: even if participants understood the consent form at enrollment, that understanding fades. They leave the clinic overwhelmed. They forget what they read. Three weeks later, they're staring at a medication they don't remember agreeing to take, wondering if the headache they're experiencing is normal.

The readability gap isn't just about the initial document. It's about ongoing access to information they can actually use.

What would it look like to close the gap?

Not simpler consent forms—though that would help. But accessible, plain-language resources that participants can return to throughout their trial. Information organized around their questions, not our documents. Answers available at 10pm when the clinic is closed.

Participants who understand their trial stay in their trial. The readability gap is the first obstacle. Ongoing comprehension is the real challenge.