Short-term efficacy of reducing screen media use on physical activity, sleep, and physiological stress in families with children aged 4-14: study protocol for the SCREENS randomized controlled trial

Abstract

Background: During the recent decade presence of digital media, especially handheld devices, in everyday life, has been increasing. Survey data suggests that children and adults spend much of their leisure on screen media, including use of social media and video services. Despite much public debate on possible harmful effects of such behavioral shifts, evidence from rigorously conducted randomized controlled trials in free-living settings, investigating the efficacy of reducing screen media use on physical activity, sleep, and physiological stress, is still lacking. Therefore, a family and home-based randomized controlled trial - the SCREENS trial - is being conducted. Here we describe in detail the rationale and protocol of this study.

Methods: The SCREENS pilot trial was conducted during the fall of 2018 and spring of 2019. Based on experiences from the pilot study, we developed a protocol for a parallel group randomized controlled trial. The trial is being conducted from May 2019 to ultimo 2020 in 95 families with children 4-14 years recruited from a population-based survey. As part of the intervention family members must handover most portable devices for a 2-week time frame, in exchange for classic mobile phones (not smartphones). Also, entertainment-based screen media use during leisure must be limited to no more than 3 hours/week/person. At baseline and follow-up, 7-day 24-h physical activity will be assessed using two triaxial accelerometers; one at the right hip and one the middle of the right thigh. Sleep duration will be assessed using a single channel EEG-based sleep monitor system. Also, to assess physiological stress (only assessed in adults), parameters of 24-h heart rate variability, the cortisol awakening response and diurnal cortisol slope will be quantified using data sampled over three consecutive days. During the study we will objectively monitor the families' screen media use via different software and hardware monitoring systems.

Discussion: Using a rigorous study design with state-of-the-art methodology to assess outcomes and intervention compliance, analyses of data from the SCREENS trial will help answer important causal questions of leisure screen media habits and its short-term influence on physical activity, sleep, and other health related outcomes among children and adults.

Trial registration: NCT04098913 at https://clinicaltrials.gov [20-09-2019, retrospectively registered].

Keywords: Physical activity; Randomized controlled trial; Screen time; Sleep; Stress.

Fig. 1

Overview of surveys and subsequent recruitment for and conduct of the SCREENS trial. A visual overview of the approximately one-and-a-half-year span of the study, which includes digitally mailing out surveys including questions regarding screen media use in children and adults. Following each survey is recruitment for and conduct of the SCREENS trial. The designation of each month on the x-axis denotes the first day of said month. Notice that the duration and timing of each wave (survey and experiment) varies, as some of the depicted waves include periods without any activity because they span holidays. However, for the sake of simplicity, this has not been changed

Fig. 2

Flow chart of participants from recruitment to statistical analyses. The flow chart above gives a broad overview of the recruitment processes via an electronic survey, initial phone contact, meeting in the families’ household, participation in the SCREENS trial and, ultimately, the statistical analyses. R; Randomization, *; Possible source of missing data, **; Stages at which participants may choose to discontinue

Fig. 3

An overview of the SCREENS trial as well as the included measurements. The figure illustrates the course of the SCREENS trial scaled in days, including the experiment phase and the timing and duration of each outcome measurement protocol. Notice that the protocol for baseline measurements and the protocol for follow-up measurements, differ only in that there is one additional day of sleep measurement at baseline (a “test” night to get acquainted with this protocol) and that the questionnaires are administrated at opposite extremes. The first meeting is an information meeting in the families’ household, whereas the second through fourth meeting take place during the trial