<p><strong>Study Objectives: </strong>Pediatricians lack tools to support families at home for the promotion of childhood sleep. We are using the Multiphase Optimization Strategy (MOST) framework to guide the development of a mobile health platform for childhood sleep promotion. The objective of this study is to demonstrate feasibility of a mobile health platform towards treating children with insufficient sleep.</p>

<p><strong>Methods: </strong>Children aged 10-12 years were enrolled (Study #1: = 30; Study #2: = 43). Participants wore a sleep tracker to measure sleep duration. Data were retrieved by a mobile health platform, programmed to send introductory messages during run-in (2 weeks) and goal achievement messages during intervention (7 weeks) periods. In study #1, participants were randomized to control, gain-framed incentive or loss-framed incentive arms. In study #2, participants were randomized to control, loss-framed incentive, normative feedback or loss-framed incentive plus normative feedback arms.</p>

<p><strong>Results: </strong>In study #1, 1514 nights of data were captured (69%) and sleep duration during the intervention was higher by an average of 21 (95% CI: -8, 51) and 34 (95% CI: 7, 61) minutes per night for the gain-framed and loss-framed arms, respectively, compared to controls. In study #2, 2,689 nights of data were captured (81%), with no major differences in average sleep duration between the control and the loss-framed or normative feedback arms.</p>

<p><strong>Conclusions: </strong>We have developed and deployed a mobile health platform that can capture sleep data and remotely communicate with families. Promising candidate intervention components will be further investigated under the of the MOST framework.</p>

<p><strong>Clinical Trials: </strong>Both studies included in this manuscript were registered at clinicaltrials.gov:-Study #1: NCT03263338-Study #2: NCT03426644.</p>

<p><strong>BACKGROUND: </strong>Pediatricians lack tools to support families at home for the promotion of childhood sleep. We are using the Multiphase Optimization Strategy (MOST) framework to guide the development of a mobile health platform for childhood sleep promotion.</p>

<p><strong>PURPOSE: </strong>Under the preparation phase of the MOST framework, to demonstrate feasibility of a mobile health platform towards treating children with insufficient sleep.</p>

<p><strong>METHODS: </strong>Children aged 10-12y were enrolled (Study #1: N=30; Study #2: N=43). Participants wore a sleep tracker to measure sleep duration. Data were retrieved by a mobile health platform, programmed to send introductory messages during run-in (2 weeks) and goal achievement messages during intervention (7 weeks) periods. In study #1, participants were randomized to control, gain-framed incentive or loss-framed incentive arms. In study #2, participants were randomized to control, loss-framed incentive, normative feedback or loss-framed incentive plus normative feedback arms.</p>

<p><strong>RESULTS: </strong>In study #1, 1,514 nights of data were captured (69%) and sleep duration during the intervention was higher by an average of 21 (95% CI: -8, 51) and 34 (95% CI: 7, 61) minutes per night for the gain-framed and loss-framed arms, respectively, compared to controls. In study #2, 2,689 nights of data were captured (81%), with no major differences in average sleep duration between the control and the loss-framed or normative feedback arms.</p>

<p><strong>CONCLUSION: </strong>We have developed and deployed a mobile health platform that can capture sleep data and remotely communicate with families. Promising candidate intervention components will be further investigated under the optimization phase of the MOST framework.</p>

<p><strong>PURPOSE: </strong>The purpose of the study was to quantify changes in sleep during the middle-to-high school transition and determine if changes in sleep differ by sociodemographic characteristics.</p>

<p><strong>METHODS: </strong>Adolescents were enrolled in eighth grade and followed into ninth grade (N&nbsp;= 110; 2,470 nights observed). The outcomes were actigraphy-estimated sleep duration, sleep onset, sleep offset, and sleep sufficiency (≥8&nbsp;hours of sleep). The exposures were school grade (eighth or ninth), school night status (school or nonschool), sex (female or male), and race (white, black, or other).</p>

<p><strong>RESULTS: </strong>On school nights, sleep duration declined by 25.8&nbsp;minutes per night (p &lt; .001) from eighth to ninth grade. There was no change in sleep duration on nonschool nights. Timing of sleep onset was 22.2&nbsp;minutes later on school nights (p &lt; .001) and 17.4&nbsp;minutes later on nonschool nights (p&nbsp;&lt;&nbsp;.001) in ninth grade. Timing of sleep offset did not change on school mornings but was 22.2&nbsp;minutes later on nonschool mornings (p &lt; .001) in ninth grade. The proportion of school nights (and nonschool nights) with sleep duration ≥8&nbsp;hours was 9.4% (38.3%) in eighth grade and 5.7% (35.9%) in ninth grade. The odds of sleeping ≥8&nbsp;hours per night was 42% lower in ninth grade, compared toeighth grade (odds ratio&nbsp;= .58; 95% confidence interval: .37, .91). Males were 59% less likely to sleep ≥8&nbsp;hours per night. Black adolescents were 51% less likely to sleep ≥8&nbsp;hours per night.</p>

<p><strong>CONCLUSIONS: </strong>Insufficient sleep is highly prevalent, especially on school nights and among male and black adolescents, and this problem worsens with the transition to high school.</p>