Informed Consent for Clinical Trials: a Comparative Study of Standard Versus Simplified Forms
Abstract
BACKGROUND: A high level of reading skill and comprehension is necessary to understand and complete most consent forms that are required for participation in clinical research studies. This study was conducted to test the hypothesis that a simplified consent form would be less intimidating and more easily understood by individuals with low-to-marginal reading skills. METHODS: During July 1996, 183 adults (53 patients with cancer or another medical condition and 130 apparently healthy participants) were tested for reading ability and then asked to read either the standard Southwestern Oncology Group (SWOG) consent form (16th grade level) or a simplified form (7th grade level) developed at Louisiana State University Medical Center-Shreveport (LSU). Participants were interviewed to assess their attitudes toward and comprehension of the form read. Then they were given the alternate consent form and asked which one they preferred and why. RESULTS: Overall, participants preferred the LSU form (62%; 95% confidence interval [CI] = 54.8%-69.2%) over the SWOG form (38%; 95% CI = 30.8%-45.2%) (P = .0033). Nearly all participants thought that the LSU form was easier to read (97%; 95% CI = 93.1%-99.9%) than the SWOG form (75%; 95% CI = 65.1%-85.7%) (P<.0001). However, the degree to which the participants understood the forms was essentially the same for the LSU form (58%; 95% CI = 48.6%-67.0%) and the SWOG form (56%; 95% CI = 43.8%-66.8%). IMPLICATIONS: These findings raise serious questions regarding the adequacy of the design of written informed consent documents for the substantial proportion of Americans with low-to-marginal literacy skills.
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Our findings support previous literature that highlights that patients prefer reading more simplified information sheets without technical jargon.
“Our findings support previous literature that highlights that patients prefer reading more simplified information sheets without technical jargon [27].”
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- Authors
- Davis, T. C., Berkel, H. J., Holcombe, R. F., Pramanik, S., & Divers, S. G.
- Affiliations
- Louisiana State University (US)
- University of California, Irvine (US)
- Venue
- JNCI Journal of the National Cancer Institute
- Publisher
- Oxford University Press (OUP)
- Published
- 1998-05-06
- Volume
- 90
- Issue
- 9
- Pages
- 668-674
- ISSN
- 0027-8874 (ISSN-L)
- 1460-2105
- OpenAlex
- W2156797205
- Cited by
- 289
- References
- 41
- Citations by year
- 2026: 5 · 2025: 5 · 2024: 6 · 2023: 10 · 2022: 6 · 2021: 7 · 2020: 8 · 2019: 13 · 2018: 9 · 2017: 20 · 2016: 11 · 2015: 8 · 2014: 12 · 2013: 17 · 2012: 18
- FWCI
- 9.50
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- JNCI Journal of the National Cancer Institute (publishedVersion)
- PubMed (publishedVersion)
- DigitalGeorgetown (Georgetown University Library) (submittedVersion)
- Topics
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Ethics in Clinical Research
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Ethics and bioethics in healthcare
- Health Sciences › Health Professions › General Health Professions › Health Literacy and Information Accessibility
- Keywords
- informed consent, reading comprehension, literacy, low literacy, informed consent forms, patient understanding, patient preferences, cancer patients, clinical trial participation
- MeSH terms
- Adult, Clinical Trials as Topic, Educational Status, Female, Humans, Informed Consent, Male, Middle Aged, Reading, Teaching Materials
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