ImportanceAlthough questionnaire-based cross-sectional research suggests that screen time before bed correlates with poor sleep, self-reported data seem unlikely to capture the complexity of modern screen use, requiring objective night-by-night measures to advance this field.ObjectiveTo examine whether evening screen time is associated with sleep duration and quality that night in youths.Design, Setting, and ParticipantsThis repeated-measures cohort study was performed from March to December 2021 in participant homes in Dunedin, New Zealand. Participants included healthy youths aged 11 to 14.9 years. Data were analyzed from October to November 2023.ExposureObjectively measured screen time, captured using wearable or stationary video cameras from 2 hours before bedtime until the first time the youth attempted sleep (shut-eye time) over 4 nonconsecutive nights. Video data were coded using a reliable protocol (κ = 0.92) to quantify device (8 options [eg, smartphone]) and activity (10 options [eg, social media]) type.Main Outcomes and MeasuresSleep duration and quality were measured objectively via wrist-worn accelerometers. The association of screen use with sleep measures was analyzed on a night-by-night basis using mixed-effects regression models including participant as a random effect and adjusted for weekends.ResultsOf the 79 participants (47 [59.5%] male; mean [SD] age, 12.9 [1.1] years), all but 1 had screen time before bed. Screen use in the 2 hours before bed had no association with most measures of sleep health that night (eg, mean difference in total sleep time, 0 minutes [95% CI, –3 to 20 minutes] for every 10 minutes more total screen time). All types of screen time were associated with delayed sleep onset but particularly interactive screen use (mean difference, 10 minutes; 95% CI, 4 to 16 minutes for every additional 10 minutes of interactive screen time). Every 10 minutes of additional screen time in bed was associated with shorter total sleep time (mean difference, –3 minutes; 95% CI, –6 to –1 minute). The mean difference in total sleep time was −9 minutes (95% CI, −16 to −2 minutes) for every 10 minutes of interactive screen use and −4 minutes (95% CI, −7 to 0 minutes) for passive screen use. In particular, gaming (mean difference, –17 minutes; 95% CI, –28 to –7 minutes for every 10 minutes of gaming) and multitasking (mean difference, −35 minutes; 95% CI, –67 to –4 minutes on nights with vs without multitasking) were associated with less total sleep time.Conclusions and RelevanceIn this repeated-measures cohort study, use of an objective method showed that screen time once in bed was associated with impairment of sleep, especially when screen time was interactive or involved multitasking. These findings suggest that current sleep hygiene recommendations to restrict all screen time before bed seem neither achievable nor appropriate.

中文翻译：

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青少年睡前屏幕使用情况以及睡眠时长和质量


重要性尽管基于问卷的横断面研究表明，睡前屏幕时间与睡眠不佳相关，但自我报告的数据似乎不太可能捕捉到现代屏幕使用的复杂性，需要客观的夜以继日的措施来推进这一领域。目的探讨青少年夜间屏幕时间是否与当晚睡眠时长和睡眠质量相关。设计、设置和参与者这项重复测量队列研究于 2021 年 3 月至 12 月在新西兰但尼丁的参与者家中进行。参与者包括 11 至 14.9 岁的健康青年。数据于 2023 年 10 月至 11 月进行分析。暴露客观测量屏幕时间，使用可穿戴或固定摄像机拍摄，从睡前 2 小时到青少年在 4 个非连续的夜晚第一次尝试睡眠（闭眼时间）。使用可靠的协议 （κ = 0.92） 对视频数据进行编码，以量化设备 （8 个选项 [例如，智能手机]）和活动 （10 个选项 [例如，社交媒体]）类型。主要结局和测量通过腕戴式加速度计客观测量睡眠持续时间和质量。使用混合效应回归模型逐夜分析屏幕使用与睡眠测量的关联，包括参与者作为随机效应，并针对周末进行调整。结果在 79 名参与者 （47 名 [59.5%] 男性;平均 [SD] 年龄，12.9 [1.1] 岁）中，除 1 名外，其余参与者在睡前都有屏幕时间。睡前 2 小时使用屏幕与当晚睡眠健康的大多数指标无关（例如，总睡眠时间的平均差异，每增加 10 分钟总屏幕时间，0 分钟 [95% CI，-3 至 20 分钟]）。 所有类型的屏幕时间都与延迟入睡有关，尤其是交互式屏幕使用（平均差，10 分钟;95% CI，每增加 10 分钟交互式屏幕时间，4 至 16 分钟）。床上每增加 10 分钟的屏幕时间与较短的总睡眠时间相关（平均差，-3 分钟;95% CI，-6 至 -1 分钟）。交互式屏幕使用每 10 分钟总睡眠时间的平均差异为 -9 分钟（95% CI，-16 至 -2 分钟），被动屏幕使用 -4 分钟（95% CI，-7 至 0 分钟）。特别是，游戏（平均差，-17 分钟;95% CI，每 10 分钟游戏 -28 至 -7 分钟）和多任务处理（平均差，-35 分钟;95% CI，-67 至 -4 分钟，有多任务处理与无多任务处理的夜晚）与较少的总睡眠时间相关。结论和相关性在这项重复测量队列研究中，客观方法的使用表明，上床后的屏幕时间与睡眠障碍相关，尤其是当屏幕时间是互动的或涉及多任务处理时。这些发现表明，目前限制睡前所有屏幕时间的睡眠卫生建议似乎既不可实现也不合适。