Screen time and sleep duration among Brazilian Quilombola schoolchildren

Screen time and sleep duration among Brazilian Quilombola schoolchildren | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Screen time and sleep duration among Brazilian Quilombola schoolchildren Laila de Sena de Souza, Lara Daniele Matos dos Santos Araujo, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7143085/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This cross-sectional study aimed to investigate the relationship between exposure to screen time and sleep duration during weekdays and weekends among schoolchildren. The sample comprises 1,004 children (7–9 years old) and adolescents (10–15 years old) from public schools in rural Quilombola communities (46.4% girls, 53.6% boys; mean age 9.4 ± SD 1.7 years). Parents provided data on sleep duration, screen time (unexposed, ≤ 2 hours/day, > 2 hours/day), and socioeconomic and demographic factors. Sleep duration was defined by the difference (in minutes) between sleep time and wake-up time. Data analysis included linear regression models stratified by age range and gender and adjusted by socioeconomic and demographic factors. The results showed that 19.3% (weekdays) and 11.7% (weekends) of participants were exposed to no screen time at all. During weekdays, 51.4% of participants were exposed to screen time for ≤ 2 hours/day and 29.3% for more than 2 hours/day; during weekends, 34.6% and 53.7% were exposed to screen time ≤ 2 hours/day and > 2 hours/day, respectively. Exposure to screen time for more than 2 hours per day during weekdays was associated with a decrease in sleep duration of 24 minutes (β = -24.2, CI95% = -42.16 to -6.23). Only sleep duration among children was associated with exposure to screen time for more than 2 hours/day (weekdays: β=-41.5, CI95%=-65.81; -17.16; weekends: β=-30.5, CI95%=-57.80 to -3.26). Both girls (β=-32.3, CI95%=-60.59 to -3.95) and boys (β=-24.1; CI95%=-46.60 to -1.60) experienced decreases in sleep duration associated with more than 2 hours of screen time, but this effect was only observed during weekdays. In conclusion, exposure to screen time is associated with reduced sleep duration among Quilombola schoolchildren during weekdays, with a significant decrease noted among children and girls on both weekdays and weekends. Screen Time Sleep Duration Child Adolescent Quilombola Communities Figures Figure 1 Figure 2 Background Sleep is an indispensable physiological need for maintaining the body's homeostasis, with positive impacts on immune health[ 1 ], reducing the risk of obesity, diabetes mellitus[ 2 ], and mortality from all causes[ 3 ]. Particularly, sleep is important during childhood and adolescence, which are periods of accelerated growth and intense cognitive development[ 4 – 6 ]. In addition to its restorative function, sleep is directly linked to hormone release, memory consolidation, and academic performance[ 7 , 8 ]. Nevertheless, the decrease in sleep duration and quality among children and adolescents has become increasingly problematic worldwide, and a concern for parents, education staff, and the health system[ 5 , 7 , 9 – 12 ]. The relationship between excessive exposure to screen time and the sleep patterns among young people has been widely studied, and the available evidence suggests that children who spend more time exposed to electronic devices as smartphones, computers, tablets, videogames, and TV tend to sleep less time per night, show restless and fragmented sleep, difficulty falling asleep and reduced efficiency of nighttime rest[ 8 , 13 ]. These effects can not only result in daytime sleepiness and poor academic performance[ 14 ] but can also trigger emotional disorders, such as irritability, mood swings, and impairments in emotional regulation. In general, evidence that most electronic devices used by children negatively impact sleep is already abundant[ 7 ]; however, as far as we know, there are no studies investigating this relationship among Quilombola communities. Most studies on this topic focus on urban populations, neglecting specific communities such as Indigenous, Riverside, and Quilombola groups, which present unique cultural, social, and environmental characteristics and traditions. The Quilombola communities in Brazil were organized by descendants of enslaved Black people, aiming to maintain their identity and cultural, religious, artistic, and culinary traditions. Mostly located in rural areas, these communities have been marked by social and economic inequalities, including poor access to basic sanitation, drinking water, education system, health services, healthy food, transportation, and the internet. Quilombola communities live in a unique context in which health variables may be different from what is observed in urban contexts, in terms of frequency and severity, and therefore need to be analyzed deeply[ 15 , 16 ]. It can be hypothesized that Quilombola communities have low exposure to screen time, which may lead to a decrease in sleep duration. Nowadays, this topic is relevant, particularly considering the effect of changes in movement behaviors among children and adolescents induced by the COVID-19 pandemic, including changes in the sleep-wake cycle, a decrease in physical activity, and an increase in screen time exposure observed worldwide[ 17 , 18 ]. In Brazil, the rates of children and adolescents adhering to the physical activity, screen time, and sleep duration guidelines were dramatically decreased in the pandemic period[ 19 ], with potential long-term effects, which must be monitored. Among the young Quilombolas included in the current research, behavioral changes in appetite and sleep patterns associated with overweight and obesity had also been identified as a result of the COVID-19 pandemic[ 20 ], which reinforces the need for further studies on this population. Considering the increasing access to technology, it is likely that the patterns of screen time exposure observed in urban areas will also emerge in rural communities, including Quilombola ones. Therefore, the current study aims to analyze the relationship between screen time exposure and sleep duration among schoolchildren attending public schools in rural Quilombola communities. Methods Design and participants This cross-sectional study utilizes data collected from a school-based survey conducted in the rural areas of Feira de Santana, Bahia, in 2022. Data collection occurred on weekdays, from Tuesday to Thursday, during school hours, between July and December 2022. Feira de Santana is the most populous and economically efficient city in the interior of Bahia, with a population of 616,279 inhabitants. (IBGE, 2022, available at: https://www.ibge.gov.br/cidades-e-estados/ba/feira-de-santana.html ). The survey included a sample of students from rural areas within Quilombola communities. Feira de Santana consists of eight rural districts: Ipuaçu , Bonfim de Feira , São José , Humildes , Tiquaruçu , Jaíba , Jaguara , and Matinha . Additionally, there are three Quilombola communities officially recognized under Presidential Decree No. 4887/2003: Lagoa Grande (located in the São José District), Matinha dos Pretos , and Fazenda Candeal II (both located in the Matinha District). In 2022, data from the Municipal Department of Education revealed that there were 19 Quilombola schools providing classes for students from 2nd to 5th grades. Among these, 16 schools were in rural areas. Overall, the total enrollment in these schools was 2,714 students, with 2,138 of them attending the rural schools. The sample size was determined using the following parameters: population of 2,138 students, an expected prevalence of 19.87% for overweight children and adolescents in Feira de Santana, a margin of error set at three percentage points, and a design effect of 1.5. Based on these parameters, the calculated sample size was 774 individuals. Additionally, a 20% adjustment was made to account for potential losses and refusals, resulting in a final targeted sample of 929 students. The cluster sampling process consisted of four main stages (Fig. 1 ): Stratification: All rural Quilombola schools were stratified based on their respective districts. Computation of Student Count: The total number of students in each district (cluster) was calculated by summing the enrollments in the selected schools. Each school’s weight within the conglomerate was determined as a percentage of the total enrollment. Sample Size Determination: The desired sample size for each school was calculated by multiplying the overall sample size by the percentage value that reflects the school's weight within the cluster. Selection of Classes and Students: Classes from 2nd to 5th grade were selected within each school, totaling 83 classes. Students were then randomly chosen from these classes. The study was conducted following the ethical guidelines outlined in Resolution No. 466/2012 by Brazil’s National Research Ethics Council and aligned with the Declaration of Helsinki. Informed consent was obtained from all participants under 16 years old, as well as their parents or guardians. Additionally, the study protocol received approval from the Research Ethics Council of the State University of Feira de Santana (Approval No. 29137320.6.0000.0053, Opinion No. 3.994.186). Measurement of the sociodemographic factors, sleep duration, and screen time exposure Parents provided data on sociodemographic factors, sleep duration, and screen time exposure during weekdays and weekends/holidays through a questionnaire. Sociodemographic factors included schoolchildren’s age and gender, the mother’s scholarship, food insecurity, and the water supply. For data analysis, age, in years, was calculated based on the date of birth and date of attendance in the survey. Food insecurity was evaluated using the following items from the Brazilian Household Food Insecurity Measurement Scale ( Escala Brasileira de Medição da Insegurança Alimentar em Domicílios - EBIA) [ 21 ]: “In the past 12 months, how often have you felt hungry but not eaten because you couldn't afford enough food?” and “In the last 12 months, how often have you eaten less than you thought you should because there wasn’t enough money to buy food?” In the data analysis, food insecurity was defined when the answers to both questions were yes. Screen time exposure was investigated by the following questions: “How much time does the student use TV, computer, video game, cell phone, or tablet per day, on school days?” and “How much time does the student use TV, computer, video games, cell phone or tablet on weekends (or holidays)?”. The answer options for both items were “Not exposed”, “≤2 hours/day”, and “>2 hours/day”. Concerning schoolchildren’s sleep duration, parents answer the following questions: “What time does the student usually go to bed at night on school days?”, “What time does the student usually wake up in the morning on school days?”, “What time does the student usually go to sleep at night on weekends/holidays?”, and “What time does the student usually wake up in the morning on weekends/holidays?”. For data analysis, sleep duration was defined by the difference between bedtime and wake-up time, in minutes. Data processing and analysis Data processing and analysis were conducted using STATA 15 (Stata Corp 2017, College Station, TX, USA). This process included descriptive statistics to summarize the sample characteristics and multiple linear models to estimate the association between screen time and sleep duration. The study employed 95% Confidence Intervals, and the significance was assumed in p value < 0.05. Potential confounders Food insecurity and access to the water supply were proxies of economic status, which may be linked to both access to electronic devices and their effects on screen time and sleep duration among participants[ 22 ]. Therefore, these factors were included in the adjusted models. Additionally, there are differences in screen-based devices exposure between girls and boys, as well as between children and adolescents[ 23 ]. Consequently, the regression models were stratified by gender and age. Results In the current study, 1,053 schoolchildren participated; however, after considering the inclusion and exclusion criteria, the analytical sample consisted of 1,004 participants (age 9.4 ± SD 1.5 years) (Figure 1). Descriptive characteristics are presented in Table 1 and Figure 2. The average sleep duration was 599.7 (±SD=80.8 minutes) and 638.7 (±SD=81.6 minutes) on weekdays and weekend, respectively. In the general sample, Quilombola schoolchildren exposed to screen time for >2 hours/day presented, on average, a decrease in sleep time of about 28 and 24 minutes during weekdays, in both crude and adjusted modeling, respectively. The association between screen time and sleep duration was statistically significant only in the crude analysis, which found that schoolchildren exposed to more than 2 hours of screen time per day experienced an average decrease of about 19 minutes in sleep time, compared to those not exposed (Table 2). Stratified analysis showed a decrease in sleep time in both crude and adjusted modeling only among children (7-9 years). In this sense, a screen time exposure >2 hours/day was associated with an average sleep duration of 41 and 30 minutes, on weekdays and weekend, respectively. There was no statistically significant association among adolescents (Table 3). Considering the analysis stratified by gender, both girls and boys presented shorter sleep durations associated with exposure to screen time for >2 hours/day on weekdays. Furthermore, boys showed reduced sleep duration when exposed to screen time for ≤2 hours/day and for >2 hours/day on weekend. However, these associations lost their statistical significance in the adjusted modeling (Table 4). Discussion The current study analyzed the associations between screen time and sleep duration among Quilombola schoolchildren from rural areas. As far as we know, it is the first study focusing on this topic with young people from a socioeconomic and historically disadvantaged group in Brazil. The findings enhance scientific knowledge and inform public health policies addressed to Quilombola communities. Additionally, in general, our findings showed that a screen time exposure for more than two hours per day is associated with an average decrease of 24 minutes in sleep duration on weekdays. These findings are aligned with international literature, which reports that excessive exposure to screen time, such as mobile, TV, computer, and videogames, is associated with a shorter sleep duration among children and adolescents[ 23 ]. Overall, the mechanism that can explain this association includes the effect of the type of light emitted by screens, which reduces the production of melatonin. Melatonin is an essential hormone for regulating sleep. Additionally, this light stimulates the central nervous system, making it difficult for children and adolescents to relax and fall asleep[ 24 ]. Sleep deprivation among children and adolescents resulting from screen exposure is a significant concern due to the long-term effects. These effects may include an increased risk of obesity, cardiovascular issues, and metabolic problems, as well as impaired mental health, poor eating habits, and difficulties in forming interpersonal relationships. Moreover, sleep deprivation can lead to daytime sleepiness, reduced concentration, decreased academic performance, and a lower likelihood of engaging in physical activities[ 25 ]. In our stratified analyses, the decrease in sleep duration was significant only for children, but not for adolescents. Studies indicate that there are differences in screen usage patterns and sensitivity to blue light exposure among different age groups[ 26 ]. In this sense, younger children are generally more impacted by the blue light effects. At the same time, children may have more consistent and stable sleep routines, whilst adolescents may have greater flexibility in their sleep schedules and higher resistance to the effects of screens. In addition, adolescents tend to have higher daily exposure to screens, particularly due to social media usage. This scenario could attenuate the effects found in a basic analysis. It is important to highlight that in recent decades, there has been a noticeable increase in the use of digital media by young people worldwide as a result of technological advances and the new dynamics of sociability. In Brazil, 53% of children and adolescents aged from 9-to-17 years regularly access the internet, especially through mobiles[ 27 ]. This scenario ranked Brazil second in the world in terms of time spent online outside of school hours[ 28 ]. Findings of the current study also showed that both girls and boys had reduced sleep duration when exposed to more than two hours of screen time per day, only on weekdays, despite socioeconomic factors. However, the effect of screen time on sleep duration was more pronounced among boys. It’s essential to note that girls and boys exhibit distinct patterns of screen time exposure[ 29 ]. Also, there are gender differences related to the type of content consumed through screens and the time spent on nighttime activities. These issues may influence the impact of screens on sleep. A previous study conducted with children and adolescents from urban and rural areas suggests that girls exhibit more daily exposure to TV, whilst boys are more exposed to videogames[ 30 ]. Another study showed that sedentary behaviors, including exposure to nighttime screen-based devices, were more pronounced among girls, whilst boys were engaged in vigorous physical activities[ 31 ]. The finding that the association between screen exposure and reduced sleep did not remain significant after adjusting for socioeconomic factors in the group of girls suggests that these factors played a more pronounced role in the relationship between screens and sleep in this group, when compared to boys. Firstly, families experiencing food insecurity, with poor access to a source of clean water, and with low maternal education - proxies for lower income - may have fewer resources to regulate children's screen time or may live in environments that hinder adequate sleep (such as shared bedrooms or noisy environments). Secondly, these families may also have less access to screen devices. This reinforces the importance of considering socioeconomic context in studies on the association between screen exposure and children's sleep duration, especially in studies including samples composed of disadvantaged population groups. Furthermore, in these lower-income contexts, girls are more responsible for performing household chores in their free time than boys, such as sweeping, washing dishes, fetching water and firewood, or taking care of younger siblings[ 32 ]. Our study has limitations that need to be commented on. Firstly, we had employed a cross-sectional design, which can´t stablish the causal link between screen time exposure and sleep duration. It can only identify associations. In addition, the data were gathered by parents' self-reports, an approach under the risk of bias, such as memory or social desirability bias. The current study also has strengths that should be highlighted, including the focus on a specific and historically marginalized population (Quilombola communities), contributing to the diversity of scientific literature, and highlighting the need to include underrepresented groups in child health research. Our findings also highlight the need to limit screen time among children, especially on weekdays, to preserve sleep duration, which potentially impacts sleep quality. Guidelines such as those of the Brazilian Society of Pediatrics, which suggest avoiding exposing children to activities that stimulate or agitate them, such as watching TV, using a computer, or a cell phone, especially close to bedtime, can be reinforced by our results when applied to Quilombola children and adolescents. Furthermore, the findings of this research suggest that interventions to limit screen time and promote improvements in healthy sleep time must consider differences in gender, age, and socioeconomic context to be effective. Conclusion Exposure to screen time for more than two hours per day has been linked to reduced sleep duration among Quilombola children and adolescents on weekdays, particularly among younger children and boys. These findings highlight the need for interventions aimed at regulating screen time, especially during the school week, when it can be difficult to recover lost sleep. Therefore, implementing strategies that promote healthy sleep habits and limit screen time is crucial to mitigate its negative effects. Declarations Author contributions The study “Screen time and sleep duration among Brazilian Quilombola schoolchildren” involved the following authors, each contributing as follows: de Souza LS, conceptualization, writing the original draft, and review. Araujo LDMS, investigation, writing the original draft, and review. Dias LAD, writing original draft, and review. Barros AKC, writing original draft, and review. de Jesus GM, conceptualization, methodology, funding acquisition, project administration, investigation, formal analysis, writing the original draft, and review. Funding The study receives financial support from Fundação de Amparo à Pesquisa do Estado da Bahia (FAPESB Public Notice Nº 005/2019, Grant term Nº. PET0004/2021). Araujo LDMS is supported by the PhD scholarship (FAPESB Process Nº 071.3711.2024.0006766-49, Grant term No. 00087776391). (CAPES process Nº888887.162643/2025-00). Data Availability The datasets generated and analyzed during this study are not publicly available due to unauthorized approval from the Research Ethics Council. However, they can be requested from the corresponding author upon reasonable request. Competing interests The authors declare no competing interests or other interests that might be perceived to influence the results and/or discussion reported in this paper. Ethics approval and consent to participate The study was conducted following the ethical guidelines outlined in Resolution No. 466/2012 by Brazil’s National Research Ethics Council and aligned with the Declaration of Helsinki. Informed consent was obtained from all participants under 16 years old, as well as their parents or guardians. Additionally, the study protocol received approval from the Research Ethics Council of the State University of Feira de Santana (Approval No. 29137320.6.0000.0053, Opinion No. 3.994.186). Clinical trial number Not applicable. Consent for publication Not applicable. References Irwin MR. Why Sleep Is Important for Health: A Psychoneuroimmunology Perspective. Annu Rev Psychol 2015;66:143–72. https://doi.org/10.1146/annurev-psych-010213-115205. Knutson KL, Van Cauter E. Associations between Sleep Loss and Increased Risk of Obesity and Diabetes . Annals of the New York Academy of Sciences 2008;1129:287–304. https://doi.org/10.1196/annals.1417.033. Cappuccio FP, D’Elia L, Strazzullo P, Miller MA. Sleep Duration and All-Cause Mortality: A Systematic Review and Meta-Analysis of Prospective Studies. Sleep 2010;33:585–92. https://doi.org/10.1093/sleep/33.5.585. Paruthi S, Brooks LJ, D’Ambrosio C, Hall WA, Kotagal S, Lloyd RM, et al. Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement of the American Academy of Sleep Medicine. Journal of Clinical Sleep Medicine 2016;12:785–6. https://doi.org/10.5664/jcsm.5866. Chaput J-P, Gray CE, Poitras VJ, Carson V, Gruber R, Olds T, et al. Systematic review of the relationships between sleep duration and health indicators in school-aged children and youth. Appl Physiol Nutr Metab 2016;41:S266–82. https://doi.org/10.1139/apnm-2015-0627. Astill RG, Van Der Heijden KB, Van IJzendoorn MH, Van Someren EJW. Sleep, cognition, and behavioral problems in school-age children: A century of research meta-analyzed. Psychological Bulletin 2012;138:1109–38. https://doi.org/10.1037/a0028204. Hale L, Guan S. Screen time and sleep among school-aged children and adolescents: A systematic literature review. Sleep Medicine Reviews 2015;21:50–8. https://doi.org/10.1016/j.smrv.2014.07.007. Brautsch LAs, Lund L, Andersen MM, Jennum PJ, Folker AP, Andersen S. Digital media use and sleep in late adolescence and young adulthood: A systematic review. Sleep Medicine Reviews 2023;68:101742. https://doi.org/10.1016/j.smrv.2022.101742. Matricciani L, Olds T, Petkov J. In search of lost sleep: Secular trends in the sleep time of school-aged children and adolescents. Sleep Medicine Reviews 2012;16:203–11. https://doi.org/10.1016/j.smrv.2011.03.005. Galland BC, Taylor BJ, Elder DE, Herbison P. Normal sleep patterns in infants and children: A systematic review of observational studies. Sleep Medicine Reviews 2012;16:213–22. https://doi.org/10.1016/j.smrv.2011.06.001. Twenge JM, Krizan Z, Hisler G. Decreases in self-reported sleep duration among U.S. adolescents 2009–2015 and association with new media screen time. Sleep Medicine 2017;39:47–53. https://doi.org/10.1016/j.sleep.2017.08.013. Carter B, Rees P, Hale L, Bhattacharjee D, Paradkar MS. Association Between Portable Screen-Based Media Device Access or Use and Sleep Outcomes: A Systematic Review and Meta-analysis. JAMA Pediatr 2016;170:1202. https://doi.org/10.1001/jamapediatrics.2016.2341. DelRosso LM, Picchietti DL, Spruyt K, Bruni O, Garcia-Borreguero D, Kotagal S, et al. Restless sleep in children: A systematic review. Sleep Medicine Reviews 2021;56:101406. https://doi.org/10.1016/j.smrv.2020.101406. Kredlow MA, Capozzoli MC, Hearon BA, Calkins AW, Otto MW. The effects of physical activity on sleep: a meta-analytic review. J Behav Med 2015;38:427–49. https://doi.org/10.1007/s10865-015-9617-6. Freitas DA, Caballero AD, Marques AS, Hernández CIV, Antunes SLNO. Saúde e comunidades quilombolas: uma revisão da literatura. Rev CEFAC 2011;13:937–43. https://doi.org/10.1590/S1516-18462011005000033. Lacerda EPD, Lima SF, Oliveira BLCAD. Health of quilombola children as a challenge for the Sustainable Development Goals: a scoping review. Rev Bras Enferm 2024;77. https://doi.org/10.1590/0034-7167-2024-0106. Kharel M, Sakamoto JL, Carandang RR, Ulambayar S, Shibanuma A, Yarotskaya E, et al. Impact of COVID-19 pandemic lockdown on movement behaviours of children and adolescents: a systematic review. BMJ Glob Health 2022;7:e007190. https://doi.org/10.1136/bmjgh-2021-007190. Qi J, Yan Y, Yin H. Screen time among school-aged children of aged 6–14: a systematic review. Glob Health Res Policy 2023;8. https://doi.org/10.1186/s41256-023-00297-z. Molleri N, Gomes Junior SC, Marano D, Zin A. Survey of the Adequacy of Brazilian Children and Adolescents to the 24-Hour Movement Guidelines before and during the COVID-19 Pandemic. IJERPH 2023;20:5737. https://doi.org/10.3390/ijerph20095737. Jesus GMD, Barros AKC, Araujo LDMDS, Schrann MMF, Dias LA, Araujo RHDO, et al. Alterações comportamentais na pandemia de COVID-19, sobrepeso e obesidade de escolares Quilombolas. Rev Bras Ativ Fís Saúde 2024;28:1–8. https://doi.org/10.12820/rbafs.28e0320. Santos LPD, Lindemann IL, Motta JVDS, Mintem G, Bender E, Gigante DP. Proposal of a short-form version of the Brazilian Food Insecurity Scale. Rev Saúde Pública 2014;48:783–9. https://doi.org/10.1590/S0034-8910.2014048005195. Etindele Sosso FA, Torres Silva F, Queiroz Rodrigues R, Carvalho MM, Zoukal S, Zarate GC. Prevalence of Sleep Disturbances in Latin American Populations and Its Association with Their Socioeconomic Status—A Systematic Review and a Meta-Analysis. JCM 2023;12:7508. https://doi.org/10.3390/jcm12247508. Hale L, Guan S. Screen time and sleep among school-aged children and adolescents: A systematic literature review. Sleep Medicine Reviews 2015;21:50–8. https://doi.org/10.1016/j.smrv.2014.07.007. Chang A-M, Aeschbach D, Duffy JF, Czeisler CA. Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proc Natl Acad Sci USA 2015;112:1232–7. https://doi.org/10.1073/pnas.1418490112. Priftis N, Panagiotakos D. Screen Time and Its Health Consequences in Children and Adolescents. Children 2023;10:1665. https://doi.org/10.3390/children10101665. Cain N, Gradisar M. Electronic media use and sleep in school-aged children and adolescents: A review. Sleep Medicine 2010;11:735–42. https://doi.org/10.1016/j.sleep.2010.02.006. Brazilian Network Information Center. Survey on internet use by children in Brazil: ICT kids online Brazil 2018. São Paulo: Comitê Gestor da Internet no Brasil; 2019. Organization for Economic Co-operation and Development (OECD). PISA (Programme for International Student Assessment) 2015 results 2017. Nuutinen T, Roos E, Ray C, Villberg J, Välimaa R, Rasmussen M, et al. Computer use, sleep duration and health symptoms: a cross-sectional study of 15-year olds in three countries. Int J Public Health 2014;59:619–28. https://doi.org/10.1007/s00038-014-0561-y. De Jesus GM, Dias LA, Barros AKC, Araujo LDMDS, Schrann MMF. Do girls wash dishes and boys play sports? Gender inequalities in physical activity and in the use of screen-based devices among schoolchildren from urban and rural areas in Brazil. BMC Public Health 2024;24. https://doi.org/10.1186/s12889-024-17672-1. Jesus GMD, Dias LA, Cerqueira PDA, Assis MAAD, Kupek E. Diferenças de gênero na avaliação qualitativa de atividades físicas e sedentárias de escolares de 7 a 10 anos no nordeste brasileiro. Revista Brasileira de Ciências do Esporte 2019. https://doi.org/10.1016/j.rbce.2018.11.002. United Nations Children’s Fund. Harnessing the Power of Data for Girls: Taking stock and looking ahead to 2030. New York: UNICEF; 2016. Tables Table 1. Sample characteristics. Variables n (%) Age 7-9 years 540 (53.8) 10-12 years 464 (46.2) Gender Girls 499 (49.7) Boys 505 (50.3) Food insecurity Not 785 (83.8) Yes 152 (16.2) Access to water supply State-owned water distribution company - EMBASA 818 (81.5) Water well, spring, or other water source 186 (18,5) Mother´s education Uneducated 41 (4.7) Elementary education 294 (34.0) High school 483 (55.8) College 47 (5.4) Table 2. Associations between screen time exposure and sleep duration on weekdays and weekend. Screen time Crude modeling Adjusted modeling* β 95%CI p value β 95%CI p value Weekdays Not exposed 1.00 1.00 ≤2 hours/day -4.41 -19.05; 10.22 0.554 -7.02 -23.42; 9.37 0.401 >2 hours/day -27.78 -43.78; -11.77 0.001 -24.19 -42.16; -6.23 0.008 Weekend Not exposed 1.00 1.00 ≤2 hours/day -8.61 -28.15; 10.93 0.388 -2.86 -23.99; 18.27 0.791 >2 hours/day -19.28 -38.03; -0.53 0.044 -18.07 -38.52; 2.39 0.083 *Adjustment variables: food insecurity, maternal education, and access to water supply. Table 3. Associations between screen time exposure and sleep duration on weekdays and weekend, stratified by age range. Screen time 7-9 years 10-12 years Crude modeling β 95%CI p value β 95%CI p value Weekdays Not exposed 1.00 1.00 ≤2 hours/day -13.00 -32.42; 6.42 0.189 -1.67 -23.61; 20.28 0.881 >2 hours/day -46.70 -68.30; -25.10 0.000 -13.64 -37.29; 10.22 0.258 Weekend Not exposed 1.00 1.00 ≤2 hours/day -14.92 -39.95; 10.10 0.242 -2.37 -33.05; 28.31 0.879 >2 hours/day -24.5 -48.71; -0.29 0.047 -14.73 -43.85; 14.40 0.321 Adjusted modeling* Weekdays Not exposed 1.00 1.00 ≤2 hours/day -13.23 -35.10; 8.64 0.235 -4.88 -30.10; 20.30 0.703 >2 hours/day -41.49 -65.81; -17.16 0.001 -15.40 -42.64; 11.84 0.267 Weekend Not exposed 1.00 1.00 ≤2 hours/day -16.67 -44.64; 11.31 0.242 13.20 -19.87; 46.26 0.433 >2 hours/day -30.53 -57.80; -3.26 0.028 -6.81 -38.58; 24.30 0.674 *Adjustment variables: food insecurity, maternal education, and access to water supply. Table 4. Associations between screen time exposure and sleep duration on weekdays and weekend, stratified by gender. Screen time Girls Boys Crude modeling β 95%CI p value β 95%CI p value Weekdays Not exposed 1.00 1.00 ≤2 hours/day -19.83 -42.39; 2.72 0.085 7.26 -11.18; 25.71 0.439 >2 hours/day -29.51 -54.94; -4.10 0.023 -30.27 -50.10; -10.48 0.003 Weekend Not exposed 1.00 1.00 ≤2 hours/day 13.47 -13.73; 40.68 0.331 -30.05 -57.76; -2.35 0.034 >2 hours/day -2.77 -29.01; 23.48 0.836 -34.85 -61.30; -8.40 0.010 Adjusted modeling* Weekdays Not exposed 1.00 1.00 ≤2 hours/day -23.40 -48.56; 1.76 0.068 8.85 -12.00; 29.70 0.404 >2 hours/day -32.27 -60.59; -3.95 0.026 -24.10 -46.60; -1.60 0.036 Weekend Not exposed 1.00 1.00 ≤2 hours/day 11.79 -17.64; 41.23 0.431 -19.10 -49.24; 11.10 0.214 >2 hours/day -12.1 -40.46; 16.30 0.403 -26.10 -55.52; 3.11 0.080 *Adjustment variables: food insecurity, maternal education, and access to water supply. Additional Declarations No competing interests reported. Supplementary Files Figure3.Suppl..docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7143085","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":492876777,"identity":"11c7e3ea-6451-4287-a79e-5e639ed5c2d6","order_by":0,"name":"Laila de Sena de Souza","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/0lEQVRIie3PMUvEMBTA8YRCXa5mrcN9h4rrfRMXH0JdzN7hPN5xkFsqrh3k+hV06fxCoC4FP4CLxfUGwaVDB3P2JuFS3QTzH5IM70cSxny+P9gx40sajhzpPbN7EKCThLvJ4RhoXTS7nY8RxvYkvDSRGq5zkyOD1PUzKNdNQtHm5lysLemy6jCZAOpblcIyv07opHqSheHI8+bF8TBAitDAillyWtUSLQm4chDRou57A0psE4L7WpajJAY0k9BAHqcXpHEuH8ZJi2aq0rMifrOiJvloiXb9RYirtt32s2l5B6uPfr6Qm2ejX7vsMPme+Vrpx/O2xW+GfT6f75/0CRGMZt0w7+vQAAAAAElFTkSuQmCC","orcid":"","institution":"State University of Feira de Santana","correspondingAuthor":true,"prefix":"","firstName":"Laila","middleName":"de Sena","lastName":"de Souza","suffix":""},{"id":492876778,"identity":"1ccbc5fa-4fae-4bcd-ae3c-39e233ffd9a7","order_by":1,"name":"Lara Daniele Matos dos Santos Araujo","email":"","orcid":"","institution":"State University of Feira de Santana","correspondingAuthor":false,"prefix":"","firstName":"Lara","middleName":"Daniele Matos dos Santos","lastName":"Araujo","suffix":""},{"id":492876779,"identity":"e3d43940-eda5-4f0a-bd88-24e7b559555b","order_by":2,"name":"Lizziane Andrade Dias","email":"","orcid":"","institution":"State University of Feira de Santana","correspondingAuthor":false,"prefix":"","firstName":"Lizziane","middleName":"Andrade","lastName":"Dias","suffix":""},{"id":492876780,"identity":"c6e5b757-6999-42bc-bc12-45bbd7eaeec3","order_by":3,"name":"Anna Karolina Cerqueira Barros","email":"","orcid":"","institution":"State University of Feira de Santana","correspondingAuthor":false,"prefix":"","firstName":"Anna","middleName":"Karolina Cerqueira","lastName":"Barros","suffix":""},{"id":492876781,"identity":"2c89e5dc-6cbc-4010-9e33-87e8bf60141d","order_by":4,"name":"Gilmar Mercês de Jesus","email":"","orcid":"","institution":"State University of Feira de Santana","correspondingAuthor":false,"prefix":"","firstName":"Gilmar","middleName":"Mercês","lastName":"de Jesus","suffix":""}],"badges":[],"createdAt":"2025-07-16 20:08:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7143085/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7143085/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88098849,"identity":"288b1ec2-8465-484c-98a0-159f3bb57807","added_by":"auto","created_at":"2025-08-01 11:11:06","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":128840,"visible":true,"origin":"","legend":"\u003cp\u003eSample flowchart.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7143085/v1/d90d78f6f5f0d1535411cd04.png"},{"id":88097115,"identity":"bcc0b74d-71e9-48f6-814c-43252551c189","added_by":"auto","created_at":"2025-08-01 11:03:06","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":36317,"visible":true,"origin":"","legend":"\u003cp\u003eScreen time during weekdays and weekend among Quilombola schoolchildren.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7143085/v1/f9e180d1cf6ca10c2243091a.png"},{"id":106750305,"identity":"f8497920-976a-4595-8d7d-0e210dc27eb7","added_by":"auto","created_at":"2026-04-13 06:43:34","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1069176,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7143085/v1/2cf43c3a-8000-41b1-8ce0-28c90cfafa9e.pdf"},{"id":88098851,"identity":"56a1bec5-a176-4ef3-8a4a-25ce9e712242","added_by":"auto","created_at":"2025-08-01 11:11:06","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":42946,"visible":true,"origin":"","legend":"","description":"","filename":"Figure3.Suppl..docx","url":"https://assets-eu.researchsquare.com/files/rs-7143085/v1/d8d98207de6cd2f9509e8e9d.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Screen time and sleep duration among Brazilian Quilombola schoolchildren","fulltext":[{"header":"Background","content":"\u003cp\u003eSleep is an indispensable physiological need for maintaining the body's homeostasis, with positive impacts on immune health[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], reducing the risk of obesity, diabetes mellitus[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], and mortality from all causes[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Particularly, sleep is important during childhood and adolescence, which are periods of accelerated growth and intense cognitive development[\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e–\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. In addition to its restorative function, sleep is directly linked to hormone release, memory consolidation, and academic performance[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eNevertheless, the decrease in sleep duration and quality among children and adolescents has become increasingly problematic worldwide, and a concern for parents, education staff, and the health system[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan additionalcitationids=\"CR10 CR11\" citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e–\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The relationship between excessive exposure to screen time and the sleep patterns among young people has been widely studied, and the available evidence suggests that children who spend more time exposed to electronic devices as smartphones, computers, tablets, videogames, and TV tend to sleep less time per night, show restless and fragmented sleep, difficulty falling asleep and reduced efficiency of nighttime rest[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. These effects can not only result in daytime sleepiness and poor academic performance[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] but can also trigger emotional disorders, such as irritability, mood swings, and impairments in emotional regulation.\u003c/p\u003e\u003cp\u003eIn general, evidence that most electronic devices used by children negatively impact sleep is already abundant[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]; however, as far as we know, there are no studies investigating this relationship among Quilombola communities. Most studies on this topic focus on urban populations, neglecting specific communities such as Indigenous, Riverside, and Quilombola groups, which present unique cultural, social, and environmental characteristics and traditions.\u003c/p\u003e\u003cp\u003eThe Quilombola communities in Brazil were organized by descendants of enslaved Black people, aiming to maintain their identity and cultural, religious, artistic, and culinary traditions. Mostly located in rural areas, these communities have been marked by social and economic inequalities, including poor access to basic sanitation, drinking water, education system, health services, healthy food, transportation, and the internet. Quilombola communities live in a unique context in which health variables may be different from what is observed in urban contexts, in terms of frequency and severity, and therefore need to be analyzed deeply[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. It can be hypothesized that Quilombola communities have low exposure to screen time, which may lead to a decrease in sleep duration.\u003c/p\u003e\u003cp\u003eNowadays, this topic is relevant, particularly considering the effect of changes in movement behaviors among children and adolescents induced by the COVID-19 pandemic, including changes in the sleep-wake cycle, a decrease in physical activity, and an increase in screen time exposure observed worldwide[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In Brazil, the rates of children and adolescents adhering to the physical activity, screen time, and sleep duration guidelines were dramatically decreased in the pandemic period[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], with potential long-term effects, which must be monitored. Among the young Quilombolas included in the current research, behavioral changes in appetite and sleep patterns associated with overweight and obesity had also been identified as a result of the COVID-19 pandemic[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e], which reinforces the need for further studies on this population.\u003c/p\u003e\u003cp\u003eConsidering the increasing access to technology, it is likely that the patterns of screen time exposure observed in urban areas will also emerge in rural communities, including Quilombola ones. Therefore, the current study aims to analyze the relationship between screen time exposure and sleep duration among schoolchildren attending public schools in rural Quilombola communities.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Methods","content":"\u003ch2\u003eDesign and participants\u003c/h2\u003e\n\u003cp\u003eThis cross-sectional study utilizes data collected from a school-based survey conducted in the rural areas of Feira de Santana, Bahia, in 2022. Data collection occurred on weekdays, from Tuesday to Thursday, during school hours, between July and December 2022.\u003c/p\u003e\n\u003cp\u003eFeira de Santana is the most populous and economically efficient city in the interior of Bahia, with a population of 616,279 inhabitants. (IBGE, 2022, available at: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.ibge.gov.br/cidades-e-estados/ba/feira-de-santana.html\u003c/span\u003e\u003c/span\u003e). The survey included a sample of students from rural areas within Quilombola communities. Feira de Santana consists of eight rural districts: \u003cem\u003eIpua\u0026ccedil;u\u003c/em\u003e, \u003cem\u003eBonfim de Feira\u003c/em\u003e, \u003cem\u003eS\u0026atilde;o Jos\u0026eacute;\u003c/em\u003e, \u003cem\u003eHumildes\u003c/em\u003e, \u003cem\u003eTiquaru\u0026ccedil;u\u003c/em\u003e, \u003cem\u003eJa\u0026iacute;ba\u003c/em\u003e, \u003cem\u003eJaguara\u003c/em\u003e, and \u003cem\u003eMatinha\u003c/em\u003e. Additionally, there are three Quilombola communities officially recognized under Presidential Decree No. 4887/2003: \u003cem\u003eLagoa Grande\u003c/em\u003e (located in the S\u0026atilde;o Jos\u0026eacute; District), \u003cem\u003eMatinha dos Pretos\u003c/em\u003e, and \u003cem\u003eFazenda Candeal II\u003c/em\u003e (both located in the Matinha District). In 2022, data from the Municipal Department of Education revealed that there were 19 Quilombola schools providing classes for students from 2nd to 5th grades. Among these, 16 schools were in rural areas. Overall, the total enrollment in these schools was 2,714 students, with 2,138 of them attending the rural schools.\u003c/p\u003e\n\u003cp\u003eThe sample size was determined using the following parameters: population of 2,138 students, an expected prevalence of 19.87% for overweight children and adolescents in Feira de Santana, a margin of error set at three percentage points, and a design effect of 1.5. Based on these parameters, the calculated sample size was 774 individuals. Additionally, a 20% adjustment was made to account for potential losses and refusals, resulting in a final targeted sample of 929 students.\u003c/p\u003e\n\u003cp\u003eThe cluster sampling process consisted of four main stages (Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e):\u003c/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003c/span\u003e\u003c/p\u003e\n\u003col style=\"list-style-type: upper-roman;\"\u003e\n \u003cli\u003eStratification: All rural Quilombola schools were stratified based on their respective districts.\u003c/li\u003e\n \u003cli\u003eComputation of Student Count: The total number of students in each district (cluster) was calculated by summing the enrollments in the selected schools. Each school\u0026rsquo;s weight within the conglomerate was determined as a percentage of the total enrollment.\u003c/li\u003e\n \u003cli\u003eSample Size Determination: The desired sample size for each school was calculated by multiplying the overall sample size by the percentage value that reflects the school\u0026apos;s weight within the cluster.\u003c/li\u003e\n \u003cli\u003eSelection of Classes and Students: Classes from 2nd to 5th grade were selected within each school, totaling 83 classes. Students were then randomly chosen from these classes.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted following the ethical guidelines outlined in Resolution No. 466/2012 by Brazil\u0026rsquo;s National Research Ethics Council and aligned with the Declaration of Helsinki. Informed consent was obtained from all participants under 16 years old, as well as their parents or guardians. Additionally, the study protocol received approval from the Research Ethics Council of the State University of Feira de Santana (Approval No. 29137320.6.0000.0053, Opinion No. 3.994.186).\u003c/p\u003e\n\u003cp\u003eMeasurement of the sociodemographic factors, sleep duration, and screen time exposure\u003c/p\u003e\n\u003cp\u003eParents provided data on sociodemographic factors, sleep duration, and screen time exposure during weekdays and weekends/holidays through a questionnaire. Sociodemographic factors included schoolchildren\u0026rsquo;s age and gender, the mother\u0026rsquo;s scholarship, food insecurity, and the water supply. For data analysis, age, in years, was calculated based on the date of birth and date of attendance in the survey.\u003c/p\u003e\n\u003cp\u003eFood insecurity was evaluated using the following items from the Brazilian Household Food Insecurity Measurement Scale (\u003cem\u003eEscala Brasileira de Medi\u0026ccedil;\u0026atilde;o da Inseguran\u0026ccedil;a Alimentar em Domic\u0026iacute;lios - EBIA)\u003c/em\u003e[\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e]: \u0026ldquo;In the past 12 months, how often have you felt hungry but not eaten because you couldn\u0026apos;t afford enough food?\u0026rdquo; and \u0026ldquo;In the last 12 months, how often have you eaten less than you thought you should because there wasn\u0026rsquo;t enough money to buy food?\u0026rdquo; In the data analysis, food insecurity was defined when the answers to both questions were yes.\u003c/p\u003e\n\u003cp\u003eScreen time exposure was investigated by the following questions: \u0026ldquo;How much time does the student use TV, computer, video game, cell phone, or tablet per day, on school days?\u0026rdquo; and \u0026ldquo;How much time does the student use TV, computer, video games, cell phone or tablet on weekends (or holidays)?\u0026rdquo;. The answer options for both items were \u0026ldquo;Not exposed\u0026rdquo;, \u0026ldquo;\u0026le;2 hours/day\u0026rdquo;, and \u0026ldquo;\u0026gt;2 hours/day\u0026rdquo;.\u003c/p\u003e\n\u003cp\u003eConcerning schoolchildren\u0026rsquo;s sleep duration, parents answer the following questions: \u0026ldquo;What time does the student usually go to bed at night on school days?\u0026rdquo;, \u0026ldquo;What time does the student usually wake up in the morning on school days?\u0026rdquo;, \u0026ldquo;What time does the student usually go to sleep at night on weekends/holidays?\u0026rdquo;, and \u0026ldquo;What time does the student usually wake up in the morning on weekends/holidays?\u0026rdquo;. For data analysis, sleep duration was defined by the difference between bedtime and wake-up time, in minutes.\u003c/p\u003e\n\u003ch2\u003eData processing and analysis\u003c/h2\u003e\n\u003cp\u003eData processing and analysis were conducted using STATA 15 (Stata Corp 2017, College Station, TX, USA). This process included descriptive statistics to summarize the sample characteristics and multiple linear models to estimate the association between screen time and sleep duration. The study employed 95% Confidence Intervals, and the significance was assumed in p value\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e\n\u003ch2\u003ePotential confounders\u003c/h2\u003e\n\u003cp\u003eFood insecurity and access to the water supply were proxies of economic status, which may be linked to both access to electronic devices and their effects on screen time and sleep duration among participants[\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e]. Therefore, these factors were included in the adjusted models. Additionally, there are differences in screen-based devices exposure between girls and boys, as well as between children and adolescents[\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e]. Consequently, the regression models were stratified by gender and age.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eIn the current study, 1,053 schoolchildren participated; however, after considering the inclusion and exclusion criteria, the analytical sample consisted of 1,004 participants (age 9.4 \u0026plusmn; SD 1.5 years) (Figure 1). Descriptive characteristics are presented in Table 1 and Figure 2. The average sleep duration was 599.7 (\u0026plusmn;SD=80.8 minutes) and 638.7 (\u0026plusmn;SD=81.6 minutes) on weekdays and weekend, respectively. In the general sample, Quilombola schoolchildren exposed to screen time for \u0026gt;2 hours/day presented, on average, a decrease in sleep time of about 28 and 24 minutes during weekdays, in both crude and adjusted modeling, respectively. The association between screen time and sleep duration was statistically significant only in the crude analysis, which found that schoolchildren exposed to more than 2 hours of screen time per day experienced an average decrease of about 19 minutes in sleep time, compared to those not exposed (Table 2).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eStratified analysis showed a decrease in sleep time in both crude and adjusted modeling only among children (7-9 years). In this sense, a screen time exposure \u0026gt;2 hours/day was associated with an average sleep duration of 41 and 30 minutes, on weekdays and weekend, respectively. There was no statistically significant association among adolescents (Table 3). Considering the analysis stratified by gender, both girls and boys presented shorter sleep durations associated with exposure to screen time for \u0026gt;2 hours/day on weekdays. Furthermore, boys showed reduced sleep duration when exposed to screen time for \u0026le;2 hours/day and for \u0026gt;2 hours/day on weekend. However, these associations lost their statistical significance in the adjusted modeling (Table 4).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe current study analyzed the associations between screen time and sleep duration among Quilombola schoolchildren from rural areas. As far as we know, it is the first study focusing on this topic with young people from a socioeconomic and historically disadvantaged group in Brazil. The findings enhance scientific knowledge and inform public health policies addressed to Quilombola communities. Additionally, in general, our findings showed that a screen time exposure for more than two hours per day is associated with an average decrease of 24 minutes in sleep duration on weekdays. These findings are aligned with international literature, which reports that excessive exposure to screen time, such as mobile, TV, computer, and videogames, is associated with a shorter sleep duration among children and adolescents[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Overall, the mechanism that can explain this association includes the effect of the type of light emitted by screens, which reduces the production of melatonin. Melatonin is an essential hormone for regulating sleep. Additionally, this light stimulates the central nervous system, making it difficult for children and adolescents to relax and fall asleep[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eSleep deprivation among children and adolescents resulting from screen exposure is a significant concern due to the long-term effects. These effects may include an increased risk of obesity, cardiovascular issues, and metabolic problems, as well as impaired mental health, poor eating habits, and difficulties in forming interpersonal relationships. Moreover, sleep deprivation can lead to daytime sleepiness, reduced concentration, decreased academic performance, and a lower likelihood of engaging in physical activities[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn our stratified analyses, the decrease in sleep duration was significant only for children, but not for adolescents. Studies indicate that there are differences in screen usage patterns and sensitivity to blue light exposure among different age groups[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. In this sense, younger children are generally more impacted by the blue light effects. At the same time, children may have more consistent and stable sleep routines, whilst adolescents may have greater flexibility in their sleep schedules and higher resistance to the effects of screens. In addition, adolescents tend to have higher daily exposure to screens, particularly due to social media usage. This scenario could attenuate the effects found in a basic analysis.\u003c/p\u003e\u003cp\u003eIt is important to highlight that in recent decades, there has been a noticeable increase in the use of digital media by young people worldwide as a result of technological advances and the new dynamics of sociability. In Brazil, 53% of children and adolescents aged from 9-to-17 years regularly access the internet, especially through mobiles[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. This scenario ranked Brazil second in the world in terms of time spent online outside of school hours[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eFindings of the current study also showed that both girls and boys had reduced sleep duration when exposed to more than two hours of screen time per day, only on weekdays, despite socioeconomic factors. However, the effect of screen time on sleep duration was more pronounced among boys. It\u0026rsquo;s essential to note that girls and boys exhibit distinct patterns of screen time exposure[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Also, there are gender differences related to the type of content consumed through screens and the time spent on nighttime activities. These issues may influence the impact of screens on sleep. A previous study conducted with children and adolescents from urban and rural areas suggests that girls exhibit more daily exposure to TV, whilst boys are more exposed to videogames[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Another study showed that sedentary behaviors, including exposure to nighttime screen-based devices, were more pronounced among girls, whilst boys were engaged in vigorous physical activities[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe finding that the association between screen exposure and reduced sleep did not remain significant after adjusting for socioeconomic factors in the group of girls suggests that these factors played a more pronounced role in the relationship between screens and sleep in this group, when compared to boys. Firstly, families experiencing food insecurity, with poor access to a source of clean water, and with low maternal education - proxies for lower income - may have fewer resources to regulate children's screen time or may live in environments that hinder adequate sleep (such as shared bedrooms or noisy environments). Secondly, these families may also have less access to screen devices. This reinforces the importance of considering socioeconomic context in studies on the association between screen exposure and children's sleep duration, especially in studies including samples composed of disadvantaged population groups. Furthermore, in these lower-income contexts, girls are more responsible for performing household chores in their free time than boys, such as sweeping, washing dishes, fetching water and firewood, or taking care of younger siblings[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eOur study has limitations that need to be commented on. Firstly, we had employed a cross-sectional design, which can\u0026acute;t stablish the causal link between screen time exposure and sleep duration. It can only identify associations. In addition, the data were gathered by parents' self-reports, an approach under the risk of bias, such as memory or social desirability bias.\u003c/p\u003e\u003cp\u003eThe current study also has strengths that should be highlighted, including the focus on a specific and historically marginalized population (Quilombola communities), contributing to the diversity of scientific literature, and highlighting the need to include underrepresented groups in child health research. Our findings also highlight the need to limit screen time among children, especially on weekdays, to preserve sleep duration, which potentially impacts sleep quality.\u003c/p\u003e\u003cp\u003e Guidelines such as those of the Brazilian Society of Pediatrics, which suggest avoiding exposing children to activities that stimulate or agitate them, such as watching TV, using a computer, or a cell phone, especially close to bedtime, can be reinforced by our results when applied to Quilombola children and adolescents. Furthermore, the findings of this research suggest that interventions to limit screen time and promote improvements in healthy sleep time must consider differences in gender, age, and socioeconomic context to be effective.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eExposure to screen time for more than two hours per day has been linked to reduced sleep duration among Quilombola children and adolescents on weekdays, particularly among younger children and boys. These findings highlight the need for interventions aimed at regulating screen time, especially during the school week, when it can be difficult to recover lost sleep. Therefore, implementing strategies that promote healthy sleep habits and limit screen time is crucial to mitigate its negative effects.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study \u0026ldquo;Screen time and sleep duration among Brazilian Quilombola schoolchildren\u0026rdquo; involved the following authors, each contributing as follows: de Souza LS, conceptualization, writing the original draft, and review. Araujo LDMS, investigation, writing the original draft, and review. Dias LAD, writing original draft, and review. Barros AKC, writing original draft, and review. de Jesus GM, conceptualization, methodology, funding acquisition, project administration, investigation, formal analysis, writing the original draft, and review.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study receives financial support from Funda\u0026ccedil;\u0026atilde;o de Amparo \u0026agrave; Pesquisa do Estado da Bahia (FAPESB Public Notice N\u0026ordm; 005/2019, Grant term N\u0026ordm;. PET0004/2021). Araujo LDMS is supported by the PhD scholarship (FAPESB Process N\u0026ordm; 071.3711.2024.0006766-49, Grant term No. 00087776391). (CAPES process N\u0026ordm;888887.162643/2025-00).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and analyzed during this study are not publicly available due to unauthorized approval from the Research Ethics Council. However, they can be requested from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests or other interests that might be perceived to influence the results and/or discussion reported in this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted following the ethical guidelines outlined in Resolution No. 466/2012 by Brazil\u0026rsquo;s National Research Ethics Council and aligned with the Declaration of Helsinki. Informed consent was obtained from all participants under 16 years old, as well as their parents or guardians. Additionally, the study protocol received approval from the Research Ethics Council of the State University of Feira de Santana (Approval No. 29137320.6.0000.0053, Opinion No. 3.994.186).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eIrwin MR. Why Sleep Is Important for Health: A Psychoneuroimmunology Perspective. Annu Rev Psychol 2015;66:143\u0026ndash;72. https://doi.org/10.1146/annurev-psych-010213-115205.\u003c/li\u003e\n\u003cli\u003eKnutson KL, Van Cauter E. \u003cem\u003eAssociations between Sleep Loss and Increased Risk of Obesity and Diabetes\u003c/em\u003e. Annals of the New York Academy of Sciences 2008;1129:287\u0026ndash;304. https://doi.org/10.1196/annals.1417.033.\u003c/li\u003e\n\u003cli\u003eCappuccio FP, D\u0026rsquo;Elia L, Strazzullo P, Miller MA. Sleep Duration and All-Cause Mortality: A Systematic Review and Meta-Analysis of Prospective Studies. Sleep 2010;33:585\u0026ndash;92. https://doi.org/10.1093/sleep/33.5.585.\u003c/li\u003e\n\u003cli\u003eParuthi S, Brooks LJ, D\u0026rsquo;Ambrosio C, Hall WA, Kotagal S, Lloyd RM, et al. Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement of the American Academy of Sleep Medicine. Journal of Clinical Sleep Medicine 2016;12:785\u0026ndash;6. https://doi.org/10.5664/jcsm.5866.\u003c/li\u003e\n\u003cli\u003eChaput J-P, Gray CE, Poitras VJ, Carson V, Gruber R, Olds T, et al. Systematic review of the relationships between sleep duration and health indicators in school-aged children and youth. Appl Physiol Nutr Metab 2016;41:S266\u0026ndash;82. https://doi.org/10.1139/apnm-2015-0627.\u003c/li\u003e\n\u003cli\u003eAstill RG, Van Der Heijden KB, Van IJzendoorn MH, Van Someren EJW. Sleep, cognition, and behavioral problems in school-age children: A century of research meta-analyzed. Psychological Bulletin 2012;138:1109\u0026ndash;38. https://doi.org/10.1037/a0028204.\u003c/li\u003e\n\u003cli\u003eHale L, Guan S. Screen time and sleep among school-aged children and adolescents: A systematic literature review. Sleep Medicine Reviews 2015;21:50\u0026ndash;8. https://doi.org/10.1016/j.smrv.2014.07.007.\u003c/li\u003e\n\u003cli\u003eBrautsch LAs, Lund L, Andersen MM, Jennum PJ, Folker AP, Andersen S. Digital media use and sleep in late adolescence and young adulthood: A systematic review. Sleep Medicine Reviews 2023;68:101742. https://doi.org/10.1016/j.smrv.2022.101742.\u003c/li\u003e\n\u003cli\u003eMatricciani L, Olds T, Petkov J. In search of lost sleep: Secular trends in the sleep time of school-aged children and adolescents. Sleep Medicine Reviews 2012;16:203\u0026ndash;11. https://doi.org/10.1016/j.smrv.2011.03.005.\u003c/li\u003e\n\u003cli\u003eGalland BC, Taylor BJ, Elder DE, Herbison P. Normal sleep patterns in infants and children: A systematic review of observational studies. Sleep Medicine Reviews 2012;16:213\u0026ndash;22. https://doi.org/10.1016/j.smrv.2011.06.001.\u003c/li\u003e\n\u003cli\u003eTwenge JM, Krizan Z, Hisler G. Decreases in self-reported sleep duration among U.S. adolescents 2009\u0026ndash;2015 and association with new media screen time. Sleep Medicine 2017;39:47\u0026ndash;53. https://doi.org/10.1016/j.sleep.2017.08.013.\u003c/li\u003e\n\u003cli\u003eCarter B, Rees P, Hale L, Bhattacharjee D, Paradkar MS. Association Between Portable Screen-Based Media Device Access or Use and Sleep Outcomes: A Systematic Review and Meta-analysis. JAMA Pediatr 2016;170:1202. https://doi.org/10.1001/jamapediatrics.2016.2341.\u003c/li\u003e\n\u003cli\u003eDelRosso LM, Picchietti DL, Spruyt K, Bruni O, Garcia-Borreguero D, Kotagal S, et al. Restless sleep in children: A systematic review. Sleep Medicine Reviews 2021;56:101406. https://doi.org/10.1016/j.smrv.2020.101406.\u003c/li\u003e\n\u003cli\u003eKredlow MA, Capozzoli MC, Hearon BA, Calkins AW, Otto MW. The effects of physical activity on sleep: a meta-analytic review. J Behav Med 2015;38:427\u0026ndash;49. https://doi.org/10.1007/s10865-015-9617-6.\u003c/li\u003e\n\u003cli\u003eFreitas DA, Caballero AD, Marques AS, Hern\u0026aacute;ndez CIV, Antunes SLNO. Sa\u0026uacute;de e comunidades quilombolas: uma revis\u0026atilde;o da literatura. Rev CEFAC 2011;13:937\u0026ndash;43. https://doi.org/10.1590/S1516-18462011005000033.\u003c/li\u003e\n\u003cli\u003eLacerda EPD, Lima SF, Oliveira BLCAD. Health of quilombola children as a challenge for the Sustainable Development Goals: a scoping review. Rev Bras Enferm 2024;77. https://doi.org/10.1590/0034-7167-2024-0106.\u003c/li\u003e\n\u003cli\u003eKharel M, Sakamoto JL, Carandang RR, Ulambayar S, Shibanuma A, Yarotskaya E, et al. Impact of COVID-19 pandemic lockdown on movement behaviours of children and adolescents: a systematic review. BMJ Glob Health 2022;7:e007190. https://doi.org/10.1136/bmjgh-2021-007190.\u003c/li\u003e\n\u003cli\u003eQi J, Yan Y, Yin H. Screen time among school-aged children of aged 6\u0026ndash;14: a systematic review. Glob Health Res Policy 2023;8. https://doi.org/10.1186/s41256-023-00297-z.\u003c/li\u003e\n\u003cli\u003eMolleri N, Gomes Junior SC, Marano D, Zin A. Survey of the Adequacy of Brazilian Children and Adolescents to the 24-Hour Movement Guidelines before and during the COVID-19 Pandemic. IJERPH 2023;20:5737. https://doi.org/10.3390/ijerph20095737.\u003c/li\u003e\n\u003cli\u003eJesus GMD, Barros AKC, Araujo LDMDS, Schrann MMF, Dias LA, Araujo RHDO, et al. Altera\u0026ccedil;\u0026otilde;es comportamentais na pandemia de COVID-19, sobrepeso e obesidade de escolares Quilombolas. Rev Bras Ativ F\u0026iacute;s Sa\u0026uacute;de 2024;28:1\u0026ndash;8. https://doi.org/10.12820/rbafs.28e0320.\u003c/li\u003e\n\u003cli\u003eSantos LPD, Lindemann IL, Motta JVDS, Mintem G, Bender E, Gigante DP. Proposal of a short-form version of the Brazilian Food Insecurity Scale. Rev Sa\u0026uacute;de P\u0026uacute;blica 2014;48:783\u0026ndash;9. https://doi.org/10.1590/S0034-8910.2014048005195.\u003c/li\u003e\n\u003cli\u003eEtindele Sosso FA, Torres Silva F, Queiroz Rodrigues R, Carvalho MM, Zoukal S, Zarate GC. Prevalence of Sleep Disturbances in Latin American Populations and Its Association with Their Socioeconomic Status\u0026mdash;A Systematic Review and a Meta-Analysis. JCM 2023;12:7508. https://doi.org/10.3390/jcm12247508.\u003c/li\u003e\n\u003cli\u003eHale L, Guan S. Screen time and sleep among school-aged children and adolescents: A systematic literature review. Sleep Medicine Reviews 2015;21:50\u0026ndash;8. https://doi.org/10.1016/j.smrv.2014.07.007.\u003c/li\u003e\n\u003cli\u003eChang A-M, Aeschbach D, Duffy JF, Czeisler CA. Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proc Natl Acad Sci USA 2015;112:1232\u0026ndash;7. https://doi.org/10.1073/pnas.1418490112.\u003c/li\u003e\n\u003cli\u003ePriftis N, Panagiotakos D. Screen Time and Its Health Consequences in Children and Adolescents. Children 2023;10:1665. https://doi.org/10.3390/children10101665.\u003c/li\u003e\n\u003cli\u003eCain N, Gradisar M. Electronic media use and sleep in school-aged children and adolescents: A review. Sleep Medicine 2010;11:735\u0026ndash;42. https://doi.org/10.1016/j.sleep.2010.02.006.\u003c/li\u003e\n\u003cli\u003eBrazilian Network Information Center. Survey on internet use by children in Brazil: ICT kids online Brazil 2018. S\u0026atilde;o Paulo: Comit\u0026ecirc; Gestor da Internet no Brasil; 2019.\u003c/li\u003e\n\u003cli\u003eOrganization for Economic Co-operation and Development (OECD). PISA (Programme for International Student Assessment) 2015 results 2017.\u003c/li\u003e\n\u003cli\u003eNuutinen T, Roos E, Ray C, Villberg J, V\u0026auml;limaa R, Rasmussen M, et al. Computer use, sleep duration and health symptoms: a cross-sectional study of 15-year olds in three countries. Int J Public Health 2014;59:619\u0026ndash;28. https://doi.org/10.1007/s00038-014-0561-y.\u003c/li\u003e\n\u003cli\u003eDe Jesus GM, Dias LA, Barros AKC, Araujo LDMDS, Schrann MMF. Do girls wash dishes and boys play sports? Gender inequalities in physical activity and in the use of screen-based devices among schoolchildren from urban and rural areas in Brazil. BMC Public Health 2024;24. https://doi.org/10.1186/s12889-024-17672-1.\u003c/li\u003e\n\u003cli\u003eJesus GMD, Dias LA, Cerqueira PDA, Assis MAAD, Kupek E. Diferen\u0026ccedil;as de g\u0026ecirc;nero na avalia\u0026ccedil;\u0026atilde;o qualitativa de atividades f\u0026iacute;sicas e sedent\u0026aacute;rias de escolares de 7 a 10 anos no nordeste brasileiro. Revista Brasileira de Ci\u0026ecirc;ncias do Esporte 2019. https://doi.org/10.1016/j.rbce.2018.11.002.\u003c/li\u003e\n\u003cli\u003eUnited Nations Children\u0026rsquo;s Fund. Harnessing the Power of Data for Girls: Taking stock and looking ahead to 2030. New York: UNICEF; 2016.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1. Sample characteristics.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"373\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVariables\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u003cstrong\u003en (%)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eAge\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003e7-9 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e540 (53.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003e10-12 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e464 (46.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eGirls\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e499 (49.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eBoys\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e505 (50.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eFood insecurity\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eNot\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e785 (83.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eYes\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e152 (16.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eAccess to water supply\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eState-owned water distribution company - EMBASA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e818 (81.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eWater well, spring, or other water source\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e186 (18,5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eMother\u0026acute;s education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eUneducated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e41 (4.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eElementary education\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e294 (34.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eHigh school\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e483 (55.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 280px;\"\u003e\n \u003cp\u003eCollege\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 93px;\"\u003e\n \u003cp\u003e47 (5.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 2. Associations between screen time exposure and sleep duration on weekdays and weekend.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"638\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eScreen time\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"bottom\" style=\"width: 229px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCrude modeling\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"bottom\" style=\"width: 229px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdjusted modeling*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026beta;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026beta;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekdays\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-4.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e-19.05; 10.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.554\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-7.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-23.42; 9.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.401\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-27.78\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e-43.78; -11.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-24.19\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-42.16; -6.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.008\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekend\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-8.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e-28.15; 10.93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e0.388\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-2.86\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-23.99; 18.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.791\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-19.28\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 106px;\"\u003e\n \u003cp\u003e-38.03; -0.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 59px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.044\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-18.07\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-38.52; 2.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 57px;\"\u003e\n \u003cp\u003e0.083\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e*Adjustment variables: food insecurity, maternal education, and access to water supply.\u003c/p\u003e\n\u003cp\u003eTable 3. Associations between screen time exposure and sleep duration on weekdays and weekend, stratified by age range.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"673\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eScreen time\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"bottom\" style=\"width: 249px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e7-9 years\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"bottom\" style=\"width: 244px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e10-12 years\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" valign=\"bottom\" style=\"width: 493px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCrude modeling\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026beta;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026beta;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekdays\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-13.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-32.42; 6.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.189\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-1.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-23.61; 20.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.881\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-46.70\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-68.30; -25.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.000\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-13.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-37.29; 10.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.258\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekend\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-14.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-39.95; 10.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.242\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-2.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-33.05; 28.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.879\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-24.5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-48.71; -0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.047\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-14.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-43.85; 14.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.321\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"6\" valign=\"bottom\" style=\"width: 493px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdjusted modeling*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekdays\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-13.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-35.10; 8.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.235\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-4.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-30.10; 20.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.703\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-41.49\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-65.81; -17.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.001\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-15.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-42.64; 11.84\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.267\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekend\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-16.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-44.64; 11.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.242\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e13.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-19.87; 46.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.433\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-30.53\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-57.80; -3.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.028\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-6.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-38.58; 24.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.674\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e*Adjustment variables: food insecurity, maternal education, and access to water supply.\u003c/p\u003e\n\u003cp\u003eTable 4. Associations between screen time exposure and sleep duration on weekdays and weekend, stratified by gender.\u003c/p\u003e\n\u003cdiv align=\"\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"674\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eScreen time\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"bottom\" style=\"width: 244px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGirls\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"bottom\" style=\"width: 250px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eBoys\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" valign=\"bottom\" style=\"width: 494px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCrude modeling\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026beta;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026beta;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e95%CI\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekdays\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-19.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-42.39; 2.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.085\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e7.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-11.18; 25.71\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.439\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-29.51\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-54.94; -4.10\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.023\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-30.27\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-50.10; -10.48\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.003\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekend\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e13.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-13.73; 40.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.331\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-30.05\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-57.76; -2.35\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.034\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-2.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-29.01; 23.48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.836\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-34.85\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-61.30; -8.40\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.010\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"6\" valign=\"bottom\" style=\"width: 494px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAdjusted modeling*\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekdays\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-23.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-48.56; 1.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.068\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e8.85\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-12.00; 29.70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.404\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-32.27\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-60.59; -3.95\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.026\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-24.10\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e-46.60; -1.60\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.036\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eWeekend\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003eNot exposed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e1.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026le;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e11.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-17.64; 41.23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.431\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-19.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-49.24; 11.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.214\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u0026gt;2 hours/day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-12.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 108px;\"\u003e\n \u003cp\u003e-40.46; 16.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.403\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 64px;\"\u003e\n \u003cp\u003e-26.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 114px;\"\u003e\n \u003cp\u003e-55.52; 3.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.080\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e*Adjustment variables: food insecurity, maternal education, and access to water supply.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Screen Time, Sleep Duration, Child, Adolescent, Quilombola Communities","lastPublishedDoi":"10.21203/rs.3.rs-7143085/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7143085/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis cross-sectional study aimed to investigate the relationship between exposure to screen time and sleep duration during weekdays and weekends among schoolchildren. The sample comprises 1,004 children (7\u0026ndash;9 years old) and adolescents (10\u0026ndash;15 years old) from public schools in rural Quilombola communities (46.4% girls, 53.6% boys; mean age 9.4\u0026thinsp;\u0026plusmn;\u0026thinsp;SD 1.7 years). Parents provided data on sleep duration, screen time (unexposed, \u0026le;\u0026thinsp;2 hours/day, \u0026gt;\u0026thinsp;2 hours/day), and socioeconomic and demographic factors. Sleep duration was defined by the difference (in minutes) between sleep time and wake-up time. Data analysis included linear regression models stratified by age range and gender and adjusted by socioeconomic and demographic factors. The results showed that 19.3% (weekdays) and 11.7% (weekends) of participants were exposed to no screen time at all. During weekdays, 51.4% of participants were exposed to screen time for \u0026le;\u0026thinsp;2 hours/day and 29.3% for more than 2 hours/day; during weekends, 34.6% and 53.7% were exposed to screen time\u0026thinsp;\u0026le;\u0026thinsp;2 hours/day and \u0026gt;\u0026thinsp;2 hours/day, respectively. Exposure to screen time for more than 2 hours per day during weekdays was associated with a decrease in sleep duration of 24 minutes (β = -24.2, CI95% = -42.16 to -6.23). Only sleep duration among children was associated with exposure to screen time for more than 2 hours/day (weekdays: β=-41.5, CI95%=-65.81; -17.16; weekends: β=-30.5, CI95%=-57.80 to -3.26). Both girls (β=-32.3, CI95%=-60.59 to -3.95) and boys (β=-24.1; CI95%=-46.60 to -1.60) experienced decreases in sleep duration associated with more than 2 hours of screen time, but this effect was only observed during weekdays. In conclusion, exposure to screen time is associated with reduced sleep duration among Quilombola schoolchildren during weekdays, with a significant decrease noted among children and girls on both weekdays and weekends.\u003c/p\u003e","manuscriptTitle":"Screen time and sleep duration among Brazilian Quilombola schoolchildren","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-01 11:03:01","doi":"10.21203/rs.3.rs-7143085/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ffb2b68b-5f3b-4892-843f-72df2ccb9bec","owner":[],"postedDate":"August 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-13T06:43:01+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-01 11:03:01","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7143085","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7143085","identity":"rs-7143085","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}