Background This study assesses how pediatric assent is conceptualized and justified within the therapeutic context. Pediatric ethicists generally agree that children should participate in medical care decisions in developmentally appropriate ways. Much attention has been paid to pediatric assent for research participation, but ambiguities persist in how assent is conceptualized and operationalized in the therapeutic context where countervailing considerations such as the child’s best interest and parental permission must also be weighed.Methods Searches were conducted in 11 databases including PubMed, Embase, (...) Cochrane Library, and Web of Science. Articles published between 2010 and 2020 were screened in COVIDENCE for meeting each of four criteria: (1) focusing on pediatric assent, (2) focusing on clinical care, (3) including normative claims, and (4) containing substantive statements about the meaning of pediatric assent. Full texts were abstracted for (1) operational definitions of assent, (2) discussion of the temporal nature of assent, (3) description of the concept of “understanding,” and (4) ethical justifications for soliciting assent. These excerpts were coded and code patterns formed themes presented in the results.Results The final analytic data set contained 29 articles. Analysis yielded three key themes. First, valid assent varies by treatment, population (e.g., younger versus older), and geographic/cultural context. Second, assent represents two distinct longitudinal processes: One involves eliciting preferences over a disease course or care episode; the other focuses on children’s developmental maturation. Third, ethical justifications for assent draw variously on instrumental and intrinsic reasons, but often remain ambiguous.Conclusions There is widespread agreement that assent is morally valuable, but there remain substantial ambiguities or disagreements about its meaning, process, and ethical justification. (shrink)