Since the middle of the 20th century, perceptions of risk have been critical to understanding engagement in volitional behavior change. However, theoretical and empirical risk perception research seldom considers the possibility that risk perceptions do not simply exist: They must be formed. Thus, some people may not have formulated a perception of risk for a hazard at the time a researcher asks them, or they may not be confident in the extent to which their perception matches reality. We describe a decade-long research program that investigates the possibility that some people may genuinely not know their risk of even well-publicized hazards. We demonstrate that indications of not knowing (i.e., “don’t know” responses) are prevalent in the U.S. population, are systematically more likely to occur among marginalized sociodemographic groups, and are associated with less engagement in protective health behaviors. “Don’t know” responses are likely indications of genuinely limited knowledge and therefore may indicate populations in need of targeted intervention. This body of research suggests that not allowing participants to indicate their uncertainty may threaten the validity and generalizability of behavior-change research. We provide concrete recommendations for scientists to allow participants to express uncertainty and to analyze the resulting data.

自 20 世纪中叶以来，风险认知对于理解参与自愿行为改变至关重要。然而，理论和实证风险认知研究很少考虑风险认知并非简单存在的可能性：它们必须形成。因此，有些人在研究人员询问时可能还没有形成对危险风险的看法，或者他们可能对自己的看法与现实相符的程度没有信心。我们描述了一项长达十年的研究计划，该计划调查了一些人可能真的不知道自己面临广为人知的危险的风险的可能性。我们证明，不知道的迹象（即“不知道”反应）在美国人口中很普遍，并且系统地更有可能发生在边缘化的社会人口群体中，并与较少参与保护性健康行为有关。“不知道”的回答可能表明知识确实有限，因此可能表明需要有针对性的干预的人群。这项研究表明，不允许参与者表明他们的不确定性可能会威胁到行为改变研究的有效性和普遍性。我们为科学家提供具体建议，让参与者表达不确定性并分析结果数据。这项研究表明，不允许参与者表明他们的不确定性可能会威胁到行为改变研究的有效性和普遍性。我们为科学家提供具体建议，让参与者表达不确定性并分析结果数据。这项研究表明，不允许参与者表明他们的不确定性可能会威胁到行为改变研究的有效性和普遍性。我们为科学家提供具体建议，让参与者表达不确定性并分析结果数据。