From awareness to action: Effects of a school-based intervention on TV viewing behavior stages and screen time guidelines knowledge in Brazilian adolescents / Da conscientização à ação: Efeitos de uma intervenção escolar nos estágios de mudança de comportamento para assistir TV e no conhecimento das diretrizes de tempo de tela em adolescentes brasileiros

The aims of the study were to verify the effect of an intervention on the stage of behavior change for TV viewing and to identify the possible mediating role of knowledge on screen time guidelines among Brazilian students. This study is a multicomponent school-based intervention conducted with 727 students (54.3% female, 13 years; 427 in the intervention group and 300 in the control group). The intervention was performed in 2017 with baseline and post-intervention assessments (over one academic year). Teacher training was carried out at the beginning of the intervention along with en-vironmental improvements, while educational curriculum such as the delivery of folders and posters were performed throughout the year. The stages of behavior change for TV viewing and knowledge of screen time guidelines were measured by a self-reported questionnaire and the structural equation modeling approach was performed. The intervention had no significant effects on stages of behavior change for TV (p = 0.744) nor did it result in significant changes on knowledge of screen time guide-lines (p = 0.741). While there was no mediation between knowledge of screen time guidelines and the effect of the intervention on stages of behavior change for TV (95%CI: -0.45;0.63), an associa-tion was found between knowledge of screen time guidelines and stages of behavior change for TV (p<0.001). In conclusion, intervention had no significant effect on the stages of behavior change for TV and no mediating effect was observed. However, enhancing awareness on screen time guidelines may positively impact the adolescent's intention to reduce TV time

Os objetivos do estudo foram verificar o efeito de uma intervenção nos estágios de mudança de comporta-mento para assistir TV e identificar o papel mediador do conhecimento sobre as recomendações de tempo de tela. A intervenção multicomponente, randomizada e controlada obteve a participação de 727 alunos em 2017 (54,3% meninas, 13 anos; 427 no grupo intervenção e 300 no grupo controle). A formação dos pro-fessores foi realizada no início da intervenção juntamente com as melhorias ambientais, enquanto as ações educativas foram realizadas ao longo do ano. Os estágios de mudança de comportamento para assistir TV e o conhecimento sobre as recomendações do tempo de tela foram mensurados por questionário auto reportado, pré e pós-intervenção (um ano letivo). Para análise dos dados foi realizada uma modelagem de equações estru-turais. Não houve efeito da intervenção nos estágios de mudança de comportamento para TV (p = 0,744) e também não houve mudanças significativas no conhecimento dos estudantes sobre as recomendações do tempo de tela (p = 0,741). Embora não tenha havido mediação entre conhecimento das recomendações do tempo de tela e o efeito da intervenção nos estágios de mudança de comportamento para TV (IC95%: -0,45;0,63), foi encontrada associação entre o conhecimento das recomendações e os estágios de mudança de comportamento para TV (p < 0,001). Conclui-se que a intervenção não teve efeito significativo nos estágios de mudança de comportamento para TV e efeito mediador. No entanto, aumentar a conscientização sobre as recomendações de tempo de tela pode impactar positivamente na intenção do adolescente de reduzir o tempo de TV

Socioeconomic inequalities in the consumption of minimally processed and ultra-processed foods in Brazilian adolescents / Desigualdades socioeconômicas no consumo de alimentos minimamente processados e ultraprocessados em adolescentes no Brasil

Abstract In this study, we evaluated socioeconomic inequalities in the consumption of in natura/minimally processed and ultra-processed foods among adolescents. We used data from the Brazilian National Survey of School Health (PeNSE), 2015. According to the self-reported consumption of beans, vegetables and fruits, a score of in natura/minimally processed foods was generated (0-21 points). Sodas, sweets, instant noodles, and ultra-processed meat were used for the score of ultra-processed foods (0-21 points). Equality indicators were gender, maternal education, and socioeconomic level. Absolute difference, ratios, concentration index and slope index of inequality were calculated. Adolescents (n=101,689, 51% girls, 14.2 years) reported a mean score of 9.97 and 11.46 for ultra-processed foods and in natura/minimally processed foods, respectively. Absolute and relative differences between adolescents with the highest and lowest socioeconomic level, there were differences of 2.64 points and 33% for consumption of in natura/minimally processed foods; and 1.48 points and 15% for ultra-processed foods. Adolescents from higher socioeconomic level ate more in natura/minimally processed foods and ultra-processed foods.

Resumo Nesse estudo, avaliamos as desigualdades socioeconômicas no consumo de alimentos in natura/minimamente processados e ultraprocessados entre adolescentes. Foram utilizados dados da Pesquisa Nacional de Saúde do Escolar (PeNSE), 2015. De acordo com o consumo autorrelatado de feijão, hortaliças e frutas, foi gerado um escore de alimentos in natura/minimamente processados (0-21 pontos). Refrigerantes, doces, macarrão instantâneo e carnes ultraprocessadas prontos para o consumo foram utilizados para a pontuação dos alimentos ultraprocessados (0-21 pontos). Os indicadores de equidade foram gênero, educação materna e nível socioeconômico. Foram calculados a diferença absoluta, razões, índice de concentração e índice de inclinação de desigualdade. Os adolescentes (n=101.689, 51% meninas, 14,2 anos) relataram escore médio de 9,97 e 11,46 para alimentos ultraprocessados e in natura/minimamente processados, respectivamente. As diferenças absolutas entre os adolescentes de alto e baixo nível socioeconômico foram mais altos e mais baixos, houve diferenças de 2,64 pontos e 33% para o consumo de alimentos in natura/minimamente processados; e 1,48 pontos e 15% para alimentos ultraprocessados. Adolescentes de níveis socioeconômicos mais elevados comeram mais alimentos in natura/minimamente processados e alimentos ultraprocessados comparado aos seus pares.

The conception, content validation, and test-retest reliability of the Questionnaire for Screen Time of Adolescents (QueST)

Abstract Objective: To analyze the content validity and the test-retest reliability of the Questionnaire for Screen Time of Adolescents (QueST). Methods: A study was conducted with high school adolescents from Southern Brazil enrolled in public education (2019). The QueST measures screen time across five constructs: studying, working/internship-related activities, watching videos, playing games, using social media/chat applications. Content validation involved consulting with experts and adolescents to evaluate whether the five constructs were clear and representing screen time behaviors, all ratings were quantified. The experts' evaluation provided Content Validity Indexes (CVI) for clarity and representativeness of the questionnaire. Students answered the QueST twice (1-week apart), and differences between applications were verified. Test-retest reliability was assessed using Intraclass Correlation Coefficients (ICC) and Bland-Altman analyses. Results: Among the experts, the CVI indicated 94% and 98% of clarity and representativeness, respectively. All items were highly clear for at least 70% of the students. Test-retest reliability was assessed with 104 students (16.3 ± 1.02 years; 66.3% girls). The ICC ranged from 0.41 (95%CI 0.24-0.56) for videos to 0.76 (95%CI 0.66-0.83) for social media/chat applications on weekdays; and from 0.24 (95%CI 0.04-0.41) for videos to 0.67 (95%CI 0.54-0.77) for social media/chat applications on weekends. The lowest mean difference was -4.6 min for working on weekdays, while the highest was 40.6 min for videos on weekends. Conclusions: The QueST proved to be fair to excellent for measuring different screen time constructs. However, the item of videos (weekends) showed poor stability. The QueST demonstrates satisfactory content validity attested by the experts and adolescents.

Prática de atividade física e participação esportiva associadas à violência em adolescentes: uma revisão sistemática / Physical activity and sports participation associated with violence in adolescents: a systematic review

RESUMO O presente estudo conduziu uma revisão da literatura que com o objetivo de investigar a relação entre a prática de atividade física (AF) e de esportes com violência e agressão entre adolescentes. Uma busca estruturada foi conduzida em três bases de dados (PubMed, Web of Science e Scielo) utilizando três campos de busca para população (adolescentes), AF/esportes e vioência/agressão. Dos 618 estudos encontrados, 555 foram selecionados por título e resumo, 63 foram lidos na íntegra e 24 foram incluídos para análise. Foi observada uma prevalência de 83% de estudos transversais, e o tamanho das amostras variou entre 210 e 71854 adolescentes. Medidas de violência e AF/esportes foram diversas. Dentre os 24 estudos analisados, seis não encontraram relação entre AF/esportes e violência, oito verificaram que AF/esportes foram fator de proteção, e 15 identificaram uma relação positiva entre AF/esportes e violência. Os achados sugerem que AF/esportes estão relacionados a uma maior exposição a conflitos e comportamentos agressivos, que podem escalar para outras relações fora do contexto da atividade feita. Contudo, o tipo de AF e o contexto parecem ter um importante papel na promoção de conflitos, com atividades coletivas com conflito direto, como futebol, oferecendo maior chance de promover agressividade comparados com atividades individuais sem conflito direto.

ABSTRACT The present study conducted a review of the literature that aimed to investigate the relationship between the practice of physical activity (PA) and sports with violence and aggression among adolescents. A structured search was conducted on three databases (PubMed, Web of Science and Scielo) using three fields for the population (adolescents), PA/sports and violence/aggression. Of the 618 studies identified, 555 were screened by the title and abstract, 63 had the full text screened and 24 were selected for inclusion and analysis. Most studies were cross-sectional (53%), and sample size varied between 210 and 71854 adolescents. Metrics of violence and PA/sports were very diverse. Of the 24 analyzed studies, six studies found no association between PA/sports and violence, eight found that PA/sports were a protective factor, and 15 found a positive relationship between PA/sports and violence. The findings suggest that PA/sports are related to higher exposition to conflicts, and aggressive behavior, which may escalate to other relationships amongst adolescents outside of the context of PA/sports. The type of PA practiced may play an important role in promoting conflicts, with team-based sports with direct conflict being more likely to promote aggressiveness compared to individual sports without direct conflicts.