Table 5.

Results from trials of multicomponent interventions to improve patient comprehension in informed consent

Source	Study country	N	Mean patient age (and range if specified)	Patients’ education	Procedure	Intervention*	Elements of patient comprehension assessed	Comprehension assessment tool	Timing of patient comprehension assessment relative to informed consent consultation*	Risk of bias for patient comprehension outcome†	Results	Group favored‡
Kostick et al. (2018)	USA	98	59.77 y (range 20 - 84)	60% ≤ high school degree/ GED, 40% ≥ some college	Left ventricular assist device implantation	Paper-based decision aid written at an 8th-grade reading level (took on average 59 minutes to review) with information about living with an LVAD, resources for patients and caregivers, narratives provided by patients and caregivers, risk and benefit information, and links to a website with supplemental informational videos developed with “extensive input of intended end users” (patients, caregivers, candidates and decliners of LVAD treatment) and clinicians involved in shared decision-making via in-depth interviews then drafted and tested following International Patient Decision Aid Standards quality indicators versus “standard education” (control)	Risks, benefits, general knowledge about procedure	20-item multiple choice LVAD knowledge scale developed and validated by the research team	Immediately and delayed	Some concerns for bias	68% intervention vs. 59% control at one week follow up, P = 0.02 No significant difference at 1 month	Intervention
Karan et al. (2014)	India	97	Not specified	Not specified	Cataract surgery	3-fold pamphlet designed by Unite for Sight, an ophthalmologist in Chennai, and a team of “visual communication specialists at a US-based university” plus patients were shown a 3D model of the eye in addition to scripted verbal informed consent read by a native Tamil speaker versus scripted verbal informed consent read by a native Tamil speaker only (control)	Risks, benefits, general knowledge about procedure	Validated 11-item true/false/don’t know quiz	Immediately and early	High risk of bias	Immediate: average difference in score from baseline 5.17 intervention vs. 1.52 control Within 24 hours: average difference in score from baseline 5.43 intervention vs. 1.06 control “P value on the order of 10−6”	Intervention

^*Immediately: within 1 hour of informed consent consultation; early: >1 hour but <24 hours of informed consent consultation, delayed: ≥ 24 hours after informed consent consultation

^†Assessed using the Cochrane Risk of Bias 2.0 tool, see Table 7 for details

^‡If a study reported an improvement in patient comprehension on a single item or multiple items of the comprehension assessment but if overall score did not improve, we considered neither or no group to be favored