Study Objectives To examine associations among instructional approaches, school start times, and sleep during the COVID-19 pandemic in a large, nationwide sample of U.S. adolescents. Methods Cross-sectional, anonymous self-report survey study of a community-dwelling sample of adolescents (grades 6–12), recruited through social media outlets in October/November 2020. Participants reported on instructional approach (in-person, online/synchronous, online/asynchronous) for each weekday (past week), school start times (in-person or online/synchronous days), and bedtimes (BT) and wake times (WT) for each identified school type and weekends/no school days. Sleep opportunity was calculated as BT-to-WT interval. Night-to-night sleep variability was calculated with mean square successive differences. Results Respondents included 5,245 racially and geographically diverse students (~50% female). BT and WT were earliest for in-person instruction; followed by online/synchronous days. Sleep opportunity was longer on individual nights students did not have scheduled instruction (>1.5 h longer for online/asynchronous than in-person). More students obtained sufficient sleep with later school start times. However, even with the same start times, more students with online/synchronous instruction obtained sufficient sleep than in-person instruction. Significantly greater night-to-night variability in sleep-wake patterns was observed for students with in-person hybrid schedules versus students with online/synchronous + asynchronous schedules. Conclusions These findings provide important insights regarding the association between instructional approach and school start times on the timing, amount, and variability of sleep in U.S. adolescents. Given the public health consequences of short and variable sleep in adolescents, results may be useful for education and health policy decision-making for post-pandemic secondary schools.

中文翻译：

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超过 5,000 名美国青少年的 COVID-19 教学方法（面对面、在线、混合）、上学时间和睡眠

研究目标 在全国范围的大型美国青少年样本中研究 COVID-19 大流行期间教学方法、上学时间和睡眠之间的关联。方法 2020 年 10 月/11 月通过社交媒体渠道招募的社区青少年（6-12 年级）样本的横断面匿名自我报告调查研究。参与者报告了教学方法（面对面、在线/同步，在线/异步）每个工作日（过去一周），学校开始时间（面对面或在线/同步日），以及每种确定的学校类型和周末/非上学日的就寝时间 (BT) 和起床时间 (WT)。睡眠机会计算为 BT-to-WT 间隔。用均方连续差异计算每晚睡眠变异性。结果 受访者包括 5, 245 名种族和地域不同的学生（约 50% 为女性）。BT 和 WT 最早用于面授；其次是在线/同步天。学生没有预定教学的个别晚上的睡眠机会更长（在线/异步比面对面的时间长 > 1.5 小时）。更多的学生在更晚的开学时间获得了充足的睡眠。然而，即使开始时间相同，在线/同步教学的学生也比面对面教学的学生获得了足够的睡眠。对于面对面混合时间表的学生，与在线/同步+异步时间表的学生相比，观察到睡眠-觉醒模式的夜间变异性显着增加。结论 这些发现为美国青少年睡眠时间、数量和可变性的教学方法和学校开始时间之间的关联提供了重要的见解。鉴于青少年睡眠时间短且多变对公共卫生的影响，结果可能有助于大流行后中学的教育和卫生政策决策。