INTRODUCTION Youth represent a high-priority group for e-cigarette health communication. This study examined youth exposure to the FDA e-cigarette warning label over four years and its association with change in youth harm perception and intention. METHODS We pooled data from the 2018-2021 National Youth Tobacco Survey (age 10-17; n=67,159). Participants were divided into four groups: never users (58.5%), susceptible nonusers (16.3%), former users (12.7%), and current users (12.5%). We examined the prevalence, time-trend, correlates, and association of youth exposure to the warning with addictiveness and harm perception, intention to use e-cigarettes, and intention to quit all tobacco products. RESULTS Only 24.5% of youth were exposed to the warning. Exposure increased from 14.9% in 2018 to 30.8% in 2019, then declined to 25.2% in 2021. Hispanic (aOR=0.76 [95 % CI=0.641 - 0.89]) and non-Hispanic Black current users (0.53 [0.40 - 0.69]) were less likely to be exposed to the warning than White current users. Youth exposure was positively associated with a higher perception of e-cigarette addictiveness (1.12 [1.04 - 1.19]) and intention to quit all tobacco products (1.28 [1.13 - 1.46]). However, exposure was negatively associated with harm perception (0.91 [0.85 - 0.96]) and intention to use e-cigarettes among e-cigarette nonusers (2.38 [1.99 - 2.84]). CONCLUSIONS The decline in youth exposure to the warning indicates wear-out effects. Strengthening the label by using compelling designs, adding themes on e-cigarette harm to youth, periodically rotating warning content, and using culturally tailored messaging may improve its impact on youth and address the racial/ethnic disparities. IMPLICATIONS The FDA e-cigarette label reached only 24.5% of youth, and exposure to the warning declined to indicate wear-out effects. Exposure was significantly lower among minorities. Exposure was associated with a higher perception of e-cigarette addictiveness and intention to quit all tobacco products. Still, it did not increase harm perception or reduce intention to use e-cigarettes among nonusers. Strengthening the label by using more compelling designs, including diverse themes focusing on e-cigarette harm relevant to youth, and periodically rotating warning content may improve its impact on youth. Continued surveillance of the implementation of e-cigarette policies is needed to ensure that they equally affect youth across racial/ethnic subpopulations.

中文翻译：

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青少年对电子烟包装上 FDA 健康警告标签的接触和反应：政策影响。

简介 青少年是电子烟健康传播的重点群体。这项研究调查了四年来青少年接触 FDA 电子烟警告标签的情况及其与青少年伤害认知和意图变化的关系。方法 我们汇总了 2018-2021 年全国青少年烟草调查（10-17 岁；n=67,159）的数据。参与者被分为四组：从不使用（58.5%）、易受影响的非用户（16.3%）、前用户（12.7%）和当前用户（12.5%）。我们研究了青少年接触警告的流行率、时间趋势、相关性以及与成瘾性和伤害感知、使用电子烟的意愿以及戒除所有烟草产品的意愿之间的关联。结果 只有 24.5% 的青少年接触过该警告。曝光率从 2018 年的 14.9% 增加到 2019 年的 30.8%，然后下降到 2021 年的 25.2%。 西班牙裔 (aOR=0.76 [95 % CI=0.641 - 0.89]) 和非西班牙裔黑人当前用户 (0.53 [0.40 - 0.69]) ）比白人当前用户更不可能受到警告。青少年接触电子烟与较高的电子烟成瘾认知（1.12 [1.04 - 1.19]）和戒除所有烟草制品的意愿（1.28 [1.13 - 1.46]）呈正相关。然而，接触与电子烟非使用者的伤害感知 (0.91 [0.85 - 0.96]) 和使用电子烟的意愿 (2.38 [1.99 - 2.84]) 呈负相关。结论 青少年接触警告的人数减少表明了疲劳效应。通过使用引人注目的设计、添加电子烟对青少年危害的主题、定期轮换警告内容以及使用针对文化的信息来强化标签，可能会提高其对青少年的影响并解决种族/民族差异。影响 FDA 电子烟标签仅覆盖了 24.5% 的青少年，并且暴露于警告并没有表明磨损效应。少数族裔的暴露程度明显较低。接触电子烟与对电子烟成瘾的更高认知以及戒除所有烟草产品的意愿相关。尽管如此，它并没有增加非使用者对电子烟的危害认知或减少使用电子烟的意愿。通过使用更引人注目的设计来强化标签，包括关注与青少年相关的电子烟危害的不同主题，并定期轮换警告内容，可能会改善其对青少年的影响。需要持续监督电子烟政策的实施情况，以确保它们平等地影响不同种族/民族亚人群的青年。