Experimenting with modifications to consent forms in comparative effectiveness research: understanding the impact of language about financial implications and key information

BACKGROUND: Informed consent forms are intended to facilitate research enrollment decisions. However, the technical language in institutional templates can be unfamiliar and confusing for decision-makers. Standardized language describing financial implications of participation, namely compensation for injury and costs of care associated with participating, can be complex and could be a deterrent for potential participants. This standardized language may also be misleading in the context of comparative effectiveness trials of standard care interventions, in which costs and risk of injury associated with participating may not differ from regular medical care. In addition, the revised U.S. Common Rule contains a new requirement to present key information upfront; the impact of how this requirement is operationalized on comprehension and likelihood of enrollment for a given study is unknown. METHODS: Two online surveys assessed the impact of (1) changes to compensation for injury language (standard vs. tailored language form) and (2) changes to the key information page (using the tailored compensation language form with standard key information vs. modified key information vs. modified key information plus financial information) on both likelihood of enrollment in and understanding of a hypothetical comparative effectiveness trial. RESULTS: Likelihood of enrolling was not observed to be different between the standard and tailored language forms in Study 1 (73 vs. 75%; p = 0.6); however, the tailored language group had a higher frequency of understanding the compensation for injury process specific to the trial (25 vs. 51%; p < 0.0001). Modifications to the key information sheet in Study 2 did not affect likelihood of enrolling (88 vs. 85 vs. 85%; p = 0.6); however, understanding of randomization differed by form (44 vs. 59 vs. 46%; p = 0.002). CONCLUSIONS: These findings suggest that refining consent forms to clarify key information and tailoring compensation for injury language to the nature of the study, especially in the context of comparative effectiveness trials, may help to improve study comprehension but may not impact enrollment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12910-021-00736-x.