What a long informed consent form costs you

How long are consent forms, and why do they keep growing?

The informed consent document has grown for decades. For oncology trials approved by one regional ethics committee in Norway, the mean consent document went from 338 words in 1987 to 1990 to 1,087 words in 2005 to 2007. The authors attribute the growth to greater complexity and especially to more material on formalities such as legal matters, financing, insurance and data storage.^⁠[2]

US forms are long too. A 2004 review of 107 oncology consent documents at one cancer institute found a mean of 2,709 words, or 10.8 pages.^⁠[3] Across 315 solid-tumor trial forms at Mayo Clinic from 2004 to 2010, the median was 5,129 words, forms from pharmaceutical sponsors were longest at a median of 5,648 words, and wordiness rose steadily over the period.^⁠[4]

Recent EU data point the same way. In a pilot study of 67 Phase III drug trials submitted in 2023, the median form ran 16 pages and 5,746 words, and industry-sponsored forms averaged 8.1 pages more than academic ones. Exploratory analyses suggested that formatting, repetition and expanded data protection sections explained more of the length differences than content did, a sign that the main drivers of length can be changed.^⁠[5]

Can patients read the forms they are asked to sign?

Often not easily. Across 798 federally funded US trials, consent forms averaged a Flesch-Kincaid grade level of 12.0, well above the 8th-grade average reading level of US adults.^⁠[6] In the 2003 national adult literacy assessment, about 22 percent of US adults had Basic health literacy and 14 percent had Below Basic.^⁠[7]

Template language is part of the cause. A 2003 survey of 114 US medical school websites found that consent template text supplied by IRBs averaged a Flesch-Kincaid grade level of 10.6 and, on average, exceeded the IRBs' own stated readability standards by 2.8 grade levels.^⁠[8] In the 2004 oncology review, none of the 107 documents was written at or below an 8th-grade level.^⁠[3]

Consent forms that are long, complex, legalistic, and have a high reading level may overwhelm prospective subjects and may inhibit reading of the full document and understanding of the relevant information.^⁠[9]

What does a long, dense form cost in comprehension, time and retention?

A meta-analysis of 103 studies found that only 52.1 percent of trial participants understood randomization and 53.3 percent understood placebo, and understanding did not improve across three decades of studies.^⁠[10] Patients rarely say so. In CISCRP's 2017 survey of 2,194 participants, only about 10 percent reported difficulty understanding the form.^⁠[11] A self-rating is not a test.

The conversation is not always the expensive part. In a VA COVID-19 trial, the consent discussion took about 10 minutes plus 5 minutes for questions, but documenting and completing paper consent averaged 4 hours.^⁠[17] That reflects pandemic isolation rules, but it is a reason to time the whole consent process, not only the discussion.

What do the regulations ask for?

Under the revised Common Rule, 45 CFR 46.116(a)(5)(i) requires that consent "begin with a concise and focused presentation of the key information" most likely to help a person decide whether to take part. Section 46.116(a)(5)(ii) adds that consent must not merely provide lists of isolated facts.^⁠[18] These 2018 Requirements took general effect on January 21, 2019.^⁠[19]

For FDA-regulated trials, 21 CFR 50.20 requires consent information in language understandable to the subject, with enough time to consider whether to take part.^⁠[20] 21 CFR 50.25 lists eight basic elements plus additional elements when appropriate.^⁠[21] Neither section sets a page count. FDA has proposed adding identical key information language at 21 CFR 50.20(e)(1), as its 2024 draft guidance notes.^⁠[22]

The March 2024 FDA and OHRP draft guidance, which is nonbinding, goes further. It recommends a key information section that is "relatively short (e.g., generally no more than a few pages)" and plain language principles for the entire consent form, such as putting the most important points first and defining technical terms.^⁠[22] Electronic consent has had joint FDA and OHRP guidance since December 2016.^⁠[23]

Which fixes improve understanding?

Better documents and more conversation have the strongest evidence. A review of 54 consent interventions tested in randomized trials found that enhanced consent forms (standardized mean difference 1.73) and extended discussion (0.53) significantly improved understanding, while multimedia approaches did not reach significance.^⁠[24] An earlier JAMA review concluded that one-on-one time with a study team member or neutral educator appeared to be the most effective approach.^⁠[25]

1. 1

   Rewrite in plain language

   Put key information first, use short sentences and tables, and define terms. The 14-page version in the randomized study got below a sixth-grade level with simpler words, shorter sentences, less passive voice and tables.^⁠[13]

2. 2

   Use teach-back, not just a signature

   Ask the patient to explain randomization, placebo, risks and the right to withdraw in their own words, then re-teach what they missed. In a review of consent for low-literacy subjects, the two studies using teach-back or teach-to-goal reached the highest comprehension.^⁠[26] Plan for repetition: in one low-literacy study, about 40 percent could teach back all eight key items on the first try.^⁠[27]

3. 3

   Offer eConsent where the IRB allows it

   A 2023 review of 35 studies with 13,281 participants found no study where paper beat eConsent on comprehension, acceptability or usability, although eConsent cycle times ran longer. Three of its five authors work for AstraZeneca or Signant Health, an eConsent provider.^⁠[28] In CISCRP's 2023 survey, participants rated the electronic form easiest to understand, yet only 32 percent reported receiving one, down from 44 percent in 2021.^⁠[29]

4. 4

   Support questions between visits

   Give patients a way to ask questions before and after the consent visit. In a pediatric genomic research program, families who chose a scripted chat-based consent tool reached consent a median 5 days after referral, versus 16 days for traditional consent, and about 96 percent of quiz takers passed its comprehension check. Families picked their own arm, so the comparison was not randomized.^⁠[30]

Question support is where Bond Health's Consent stage fits. Bond gives patients plain-language explanations, answers their questions, supports comprehension, and escalates to staff when a question needs a person. The site and PI still obtain consent.^⁠[1] If you add AI support to consent, describe it to your IRB. The IRB submission language template is a starting point.

How do you know if your consent process is working?

Track these measures per study and per consent version. Much of the raw data is already in your CTMS, regulatory binder or visit notes.

Bond's dashboard reports patients matched, contacted, pre-screened, consented and randomized, along with time to enrollment, so the consent step can be read against the funnel around it.^⁠[1] For what must be approved before any outreach starts, see the guide to IRB and HIPAA rules for patient outreach.

What should I do this week?

• Pull the consent form for your highest-enrolling study. Record its page count, word count and Flesch-Kincaid grade level.
• Compare its opening pages with the key information requirement in 45 CFR 46.116(a)(5)(i), or with the 2024 draft guidance for an FDA-only study. If key information is not up front and concise, raise it with the sponsor and IRB.
• Ask coordinators which sections they re-explain most often. Those are the first rewrite candidates.
• Add teach-back for randomization, placebo, risks and the right to withdraw to your consent visit checklist.
• Start logging consent visit length and withdrawal reasons for the next several consents.
• Ask the sponsor whether a plain-language or eConsent version exists, and whether your IRB has approved it.