Medically complex titles and descriptions found on clinical trial websites and online applications present a barrier to comprehension for users from the general public. In this study, we examine the effectiveness of plain language trial descriptions for user comprehension of basic trial details. Two hundred seventeen volunteers recruited from patient waiting areas completed 441 user tests of ten plain language trial descriptions. The majority of volunteers adequately comprehended the cancer type and basic inclusion/exclusion criteria from plain language trial descriptions. Difficulty comprehending the treatment being studied was seen in seven of ten descriptions tested. Revision and retesting of the seven trial descriptions showed continued user challenges in comprehending the treatment being studied. Plain language clinical trial descriptions integrated into a website/app allowed users to understand basic inclusion/exclusion criteria. Despite plain language used, discerning the treatment being studied may be difficult for some users. Integration of plain language descriptions into clinical trial online applications can help users understand trial basics. Further research regarding effective use of plain language to communicate the treatment being studied is needed.
Keywords: App; Cancer clinical trials; Clinical trial descriptions; Clinical trials; Comprehension; General public; Health literacy; Plain language; User testing; Users; Website.