ABSTRACT
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.
ABSTRACT
Abstract This review updated data on sedentary behavior in Brazilian children and adolescents for the Brazil's Report Card 4.0. The searching was carried out in eight databases (PubMed, Scopus, Web of Science, LILACS, SPORTDiscus, BIREME, Scielo, and Google Scholar), based on the the following criteria: original research; samples including Brazilian children and adolescents; to be a observational survey with the prevalence of at least one component of sedentary behavior. In this updated review were included 118 studies (corresponding to 159 papers), being 71 studies (104 papers) previously reviewed in the Report Card 3.0 and 47 studies (55 papers) found in update from 2018 to 2019. Screen time (34.7%) and TV viewing (28.2%) remains the most investigated components, however, two studies investigated cell phone use, and there was an increase in other types of sedentary behavior such as sitting time (from 9% to 25.6%). We found only four studies involving pre-scholars, but four of them covered almost all age groups. Self-reported questionnaire was the instrument more used; however, increased the studies using accelerometers (from 2 to 8 studies). The cut-off point more frequent was 2 hours/day (47.5%), but the use of other measures doubled. Almost 70% of the studies reported that less than 50% (general range: 9.4% to 97.7%) of individuals had < 2 hours/day of sedentary behavior. The updated review found few studies with prescholars and children; using validated instruments; using accelerometers, with standardization of cutoff points, and prevalences very close to what was observed in the previous review.
Resumo Este revisão atualiza dados de comportamento sedentário em crianças e adolescentes brasileiros para o Report Card Brasil 4.0. A busca foi realizada em oito bases de dados (PubMed, Scopus, Web of Science, LILACS, SPORTDiscus, BIREME, Scielo, and Google Scholar) usando os seguintes critérios: artigos originais; amostras incluindo crianças e adolescentes; estudos observacionais que estimaram a prevalência de pelo menos um componente do CS. Nesta atualização foram incluídos 118 estudos (com publicação de 159 artigos), sendo 71 (104 artigos) revisados anteriormente no Report Card 3.0 e 47 estudos (55 artigos) encontrados na atualização de 2018 a 2019. O tempo de tela (34,7%) e de TV (28,2%) continuam sendo os componentes mais investigados, entretanto, dois estudos investigaram o uso de celular e houve aumento em outros comportamentos sedentários, como o tempo sentado (de 9% para 25,6%). Foram encontrados somente quatro estudos com pré-escolares, mas quatro deles cobriam quase todas as idades. O questionário foi o instrumento mais utilizado; no entanto, aumentou o número de estudos usando acelerômetros (de 2 para 8). O ponto de corte mais frequente foi 2 horas/dia (47,5%), mas o uso de outros medidas duplicou. Quase 70% dos estudos relatou que menos de 50% (variação geral: 9,4% a 97,7%) dos adolescentes atendem às recomendações (<2 horas / dia) de comportamento sedentário. A revisão atualizada mostra ainda poucos estudos com pré-escolares e crianças, com o uso de instrumentos validados, com o uso de acelerômetros, com padronização de pontos de corte, e prevalências muito próximas do observado na revisão anterior.