SynthesisPloS one2024
Participants' understanding of informed consent in clinical trials: A systematic review and updated meta-analysis.
Synthesis in PloS one, 2024. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It has been retracted, and should not be counted. Cited by 11 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
11 citing papers in PubMed.
- A randomized control trial of re-designed and shorter research informed consent forms to improve comprehension.Clinical trials (London, England) · 2026Trial
- Feasibility, acceptability, and usability of a patient decision aid for participation in the DAHANCA 35 proton radiotherapy trial: A qualitative study.Technical innovations & patient support in radiation oncology · 2026Article
- Article
- Piloting an ICU follow-up clinic - qualitative process evaluation alongside a feasibility study.Pilot and feasibility studies · 2026Article
- Emergency consent pathways in acute ischemic stroke trials: determinants, consequences, and stakeholder attitudes-an evidence-mapping study.BMC medical ethics · 2026Article
- Quality of Informed Consent via Telemedicine Compared With In-Person for Clinical Cancer Research.JCO oncology practice · 2026Article
- Ethical oversight of AI-driven paediatric trials: a proactive, risk-sensitive interim review model.Frontiers in digital health · 2026Article
- Adults with Intellectual Disability and Consent to Precision Medicine Research: Using Supported Decision-Making to Facilitate First-Person Consent.The Journal of law, medicine & ethics : a journal of the American Society of Law, Medicine & Ethics · 2026Article
- Digital Informed Consent/Assent in Clinical Trials Among Pregnant Women, Minors, and Adults: Multicountry Cross-Sectional Evaluation of Comprehension and Satisfaction.JMIR human factors · 2025Article
- Retraction: Participants' understanding of informed consent in clinical trials: A systematic review and updated meta-analysis.PloS one · 2025Article
- Patients' Information Needs for Informed Consent to Participate in First-in-Human Pig Kidney Xenotransplant Clinical Trials: A Mixed Methods Study.XenotransplantationArticle
Corrections and comments
- Retraction · 2025-06-03Concerns/Issues about Article · Investigation by Journal/Publisher · Unreliable Results and/or Conclusions ·
- Retracted
Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Obtaining written informed consent from participants before enrolment in a study is essential. A previous study showed that only 50% of the participants in clinical trials understood the components of informed consent, and the methods of participants' understanding of informed consent were controversial. This updated meta-analysis aimed to estimate the proportion of participants in clinical trials who understand the different informed consent components. PubMed, EMBASE, the Cochrane Library, and Scopus were searched till April 2023. Therapeutic misconception, ability to name one risk, knowing that treatments were being compared, and understanding the nature of the study, the purpose of the study, the risks and side-effects, the direct benefits, placebo, randomization, voluntariness, freedom to withdraw, the availability of alternative treatment if withdrawn from the trial, confidentiality, compensation, or comprehension were evaluated. This meta-analysis included 117 studies (155 datasets; 22,118 participants). The understanding of the risks and side-effects was investigated in the largest number of studies (n = 100), whereas comparehension was investigated in the smallest number (n = 11). The highest proportions were 97.5%(95% confidence interval (CI): 97.1-97.9) for confidentiality, 95.9% (95% confidence interval (CI): 95.4-96.4) for compensation, 91.4% (95% CI: 90.7-92.1) for the nature of study, 68.1% (95% CI: 51.6-84.6) for knowing that treatments were being compared, and 67.3% (95% CI: 56.6-78) for voluntary nature of participants. The smallest proportions were the concept of placebo (4.8%, 95%CI: 4.4-5.2) and randomization(39.4%, 95%CI: 38.3-40.4). Our findings suggested that most participants understood the fundamental components of informed consent (study confidentiality, nature, compensation, voluntariness, and freedom to withdraw). The understanding of other components, such as placebo and randomization was less satisfactory.
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.