Simplification improves understanding of informed consent information in clinical trials regardless of health literacy level

Background: This study evaluated the effect of a simplified informed consent form for clinical trials on the understanding and efficacy of informed consent information across health literacy levels. Methods: A total of 150 participants were randomly assigned to one of two groups and provided with either standard or simplified consent forms for a cancer clinical trial. The features of the simplified informed consent form included plain language, short sentences, diagrams, pictures, and bullet points. Results: Levels of objective and subjective understanding were significantly higher in participants provided with simplified informed consent forms relative to those provided with standard informed consent forms. The interaction effects between type of consent form and health literacy level on objective and subjective understanding were nonsignificant. Conclusion: Simplified informed consent was effective in enhancing participant's subjective and objective understanding regardless of health literacy.