Importance Children and adults spend large amounts of their leisure time using screen media, which may affect their health and behavior. Objective To investigate the effect of reducing household recreational screen media use on physical activity and sleep in children and adults. Design, Setting, and Participants This was a cluster randomized clinical trial with a 2-week follow-up. Enrollment began on June 6, 2019, and ended on March 30, 2021. This study included a population-based sample from 10 Danish municipalities. A total of 89 families (181 children and 164 adults) were recruited based on a population-based survey on screen media habits in families with children. To be eligible, the responding parent had to list self-reported recreational screen use greater than the 40th percentile of recreational screen time use in the source population (>2.4 hours per day). In addition, the parent had to be full-time employed (with no regular night shifts) or enrolled in full-time education. Interventions Families were randomly assigned to the screen media reduction intervention (45 families, 86 children, 82 adults) designed to ensure participant compliance to a maximum use of screen media (≤3 hours per week) for a 2-week period. Families randomly assigned to the control group (44 families, 95 children, 82 adults) were instructed to carry on as usual. Main Outcomes and Measures The primary outcome was between-group difference in leisure nonsedentary activity (in minutes per day) measured by combined thigh and waist accelerometry. Secondary outcomes included other physical activity and sleep parameters measured by single-channel electroencephalography. Results Among the 89 randomized families (intervention group [45 families]: 86 children; mean [SD] age, 8.6 [2.7] years; 44 boys [51%]; 42 girls [49%]; control group [44 families]: 95 children, mean [SD] age, 9.5 [2.5] years; 38 boys [40%]; 57 girls [60%]), 157 children (87%) had complete data on the primary outcome. Eighty-three children (97%) in the intervention group were compliant to the screen use reduction during the intervention. The mean (SD) change in leisure nonsedentary activity in the intervention group was 44.8 (63.5) minutes per day and in the control group was 1.0 (55.1) minute per day (intention-to-treat between-group mean difference, 45.8 minutes per day; 95% CI, 27.9-63.6 minutes per day; P < .001). No significant between-group mean differences were observed between intervention and control for the electroencephalography-based sleep outcomes. Conclusions and Relevance In this cluster randomized clinical trial, a recreational screen media reduction intervention resulted in a substantial increase in children's engagement in physical activity. The large effect size suggests that the high levels of recreational screen media use seen in many children should be a public health concern. Trial Registration ClinicalTrials.gov Identifier: NCT04098913.

中文翻译：

---

限制娱乐屏幕媒体的使用对有孩子的家庭的身体活动和睡眠的影响：一项整群随机临床试验。

重要性 儿童和成人将大量闲暇时间花在使用屏幕媒体上，这可能会影响他们的健康和行为。目的 调查减少家庭娱乐性屏幕媒体使用对儿童和成人身体活动和睡眠的影响。设计、设置和参与者 这是一项整群随机临床试验，随访时间为 2 周。招募从 2019 年 6 月 6 日开始，到 2021 年 3 月 30 日结束。这项研究包括来自丹麦 10 个城市的人口样本。根据对有孩子的家庭的屏幕媒体习惯进行的人口调查，总共招募了 89 个家庭（181 个儿童和 164 个成人）。要符合资格，做出回应的父母必须列出自我报告的消遣性屏幕使用情况，超过源人群中消遣性屏幕使用时间的第 40 个百分位（每天 > 2.4 小时）。此外，父母必须是全职工作（没有固定的夜班）或接受全日制教育。干预 家庭被随机分配到屏幕媒体减少干预（45 个家庭、86 个儿童、82 个成人），旨在确保参与者在 2 周的时间内最大程度地使用屏幕媒体（每周≤3 小时）。随机分配到对照组的家庭（44 个家庭，95 个儿童，82 个成人）被指示照常进行。主要结果和测量 主要结果是通过联合大腿和腰部加速度计测量的休闲非久坐活动（以分钟/天计）的组间差异。次要结果包括通过单通道脑电图测量的其他身体活动和睡眠参数。结果 在 89 个随机分配的家庭中（干预组 [45 个家庭]：86 名儿童；平均 [SD] 年龄，8.6 [2.7] 岁；44 个男孩 [51%]；42 个女孩 [49%]；对照组 [44 个家庭]： 95 名儿童，平均 [SD] 年龄，9.5 [2.5] 岁；38 名男孩 [40%]；57 名女孩 [60%]），157 名儿童 (87%) 具有主要结局的完整数据。干预组中的 83 名儿童 (97%) 在干预期间对减少使用屏幕表示顺从。干预组休闲非久坐活动的平均 (SD) 变化为每天 44.8 (63.5) 分钟，而对照组为每天 1.0 (55.1) 分钟（意向性治疗组间平均差异为 45.8 分钟/天）天；95% CI，每天 27.9-63.6 分钟；P < .001）。对于基于脑电图的睡眠结果，在干预组和对照组之间没有观察到显着的组间平均差异。结论和相关性 在这项整群随机临床试验中，一项减少娱乐性屏幕媒体的干预措施导致儿童参与体育活动的人数大幅增加。较大的效应值表明，许多儿童大量使用娱乐性屏幕媒体应该是一个公共卫生问题。试验注册 ClinicalTrials.gov 标识符：NCT04098913。娱乐屏幕媒体减少干预导致儿童参与体育活动的大幅增加。较大的效应值表明，许多儿童大量使用娱乐性屏幕媒体应该是一个公共卫生问题。试验注册 ClinicalTrials.gov 标识符：NCT04098913。娱乐屏幕媒体减少干预导致儿童参与体育活动的大幅增加。较大的效应值表明，许多儿童大量使用娱乐性屏幕媒体应该是一个公共卫生问题。试验注册 ClinicalTrials.gov 标识符：NCT04098913。