Evidence Hub

Measuring and evaluating participant understanding of consent processes in clinical trials: a systematic review

Faisal S, Wade J, Dos Santos J, Lane JA, Birchley G, Dawson S, Dawson S

Trials, 2026

1 citation

Abstract

Background: Informed consent (IC) is essential for maintaining participant autonomy in clinical trials by ensuring participants are fully informed. However, inconsistent oversight of spoken information provision and participant comprehension of both written and spoken information can lead to significant gaps in participant understanding and recall of critical trial details. This systematic review (SR) evaluates existing tools or approaches that measure participant understanding during the IC process. It will further focus on the quality of data regarding the validity and reliability of these methods.

Methods: Relevant primary studies were identified through searching electronic databases from inception to March 2023. Studies included adults who had undergone the IC process for research. Following screening, data extraction was performed using a customised Microsoft Excel template, focusing on characteristics including validity, reliability, and patient and public involvement in the development of tools/measures used to assess participant understanding. Narrative synthesis was used to descriptively organise and summarise findings across studies, including study characteristics, assessment timing, and types of tools or approaches used, while psychometric properties were evaluated using the COSMIN (COnsensus-based Standards for the selection of health Measurement INstruments) framework.

Results: Of the 6526 records screened, 261 studies were retrieved for full-text screening…

How strong is the evidence?

Evidence Hub reads this as a systematic review, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free