NRG Clinical Trial Consent Forms: Consenting Ourselves and Forgetting the Patient

Abstract

Multiple studies have shown that short consent forms with appropriately written patient information improve clinical trial enrollment and patient comprehension. The Department of Health and Human Services recommends that consent forms be written at a 7th grade level and be 7 pages or less in length. We hypothesized that NRG clinical trial consent forms would be written at a 7th grade level and less than 7 pages in length. We accessed the most recent consent forms for 20 open NRG clinical trials. We performed a readability analysis of these consents of 10 commonly used readability tests: the New Dale–Chall Test, Flesch Reading Ease Score, Flesch-Kinkaid Grade Level, FORCAST test, Fry Score, Simple Measure of Gobbledygook, Gunning Frequency of Gobbledygook, New Fog Count, Raygor Readability Estimate, and Coleman-Liau Index. These readability tests take into account sentence length, syllables per a word, and complexity of grammar. We also measured the number of words per a document and consent length in pages. We sought to test the hypothesis that the readability of patient information found on NRG clinical trial consent forms was written at the 7thgrade level and condensed to less than 7 pages per consent. We were able to access 20 NRG clinical trial consent forms. Per review, these consent form language was all based on similar templates but adapted for each NRG trial. The average words per a consent form were 4,940 (range 2,263 – 6,927). Each consent form was an average of 12.4 pages (sd 2.9) in length (range 6-16 pages). This was significantly above the target length of less than 7 pages (p<0.01). The readability of consent formed varied across different tests (see Table 1), but were universally above the 7thgrade level. A composite measure of grade level was constructed using the readability measures that provide a single grade level output. These measures were strongly correlated and formed a reliable measure (SI alpha = 0.96). A one-sample t-test found that the average grade level of these documents (10.32, sd = 0.51) was significantly higher than a seventh grade reading level, t (19) = 28.92, p < .001. NRG consent forms are more complex for patients than recommended. At their current length, taking into account average reading speeds, it may take a patient 20 minutes to read through the consent form only once. This may impede patient understanding and discourage NRG trial enrollment. Simplifying of consent language may help encourage comprehension and trial enrollment.Abstract 2981; Table 1Reading TestGrade Mean [Min, Max]Coleman-Liau9.8 [9, 10.6]Flesh-Kincaid10.3 [9.3, 11.9]FORCAST10.3 [9.8, 10.5]Fry10 [10, 12]Gunning Fog11.4 [10.4, 13.3]New Dale-Chall8.3 [7.5, 9.5]New Fog Count9.3 [8. 11.5]Raygor Estimate9 [8, 10]SMOG12.2 [11.5, 13.4]Flesch Reading Ease test does not provide a grade level output. Flesch Reading Ease score 57 (53-63). 60-70 corresponds to 7th grade. New Dale-Chall provides an individual score range (shown as a mean above). Open table in a new tab