To identify ways to improve adolescents' understanding of informed assent by exploring adolescent comprehension of concepts common to all clinical trials as well as those specific to a human immunodeficiency virus vaccine trial.
Qualitative descriptive study.
Healthy adolescents aged 15 to 17 years in 8 focus groups.
Focus groups were conducted using a semistructured interview guide. Digital recordings of the groups were transcribed verbatim.
Textual data were categorized by 2 investigators using directed qualitative content analysis techniques. Major themes and subthemes were identified, and representative quotes were selected.
The general research concepts that were most difficult for teens to understand were placebo and randomization. The most difficult vaccine trial concepts were how a vaccine works and that a vaccine is used for prevention rather than treatment. The most difficult human immunodeficiency virus vaccine–specific trial concept was that standard human immunodeficiency virus antibody tests might provide a false-positive result for participants receiving the test vaccine. Focus group participants wanted to be informed about adverse effects, trial procedures, and whether previous research had been performed before making a decision about trial participation.
Many clinical trial concepts were difficult for teens to understand. Attention needs to be directed toward developing effective ways to explain these concepts to adolescents participating in future human immunodeficiency virus vaccine and other clinical trials.