Psychometric analysis of the Brazilian-version Kidscreen-27 questionnaire.

BACKGROUND: The objective of this study was to verify the reliability, discriminatory power and construct validity of the Kidscreen-27 questionnaire in Brazilian adolescents. METHODS: Adolescents that participated of the pilot study (210 adolescents; 52.9% boys; 13.7 years old) and of the baseline (816 participants; 52.7% girls; 13.1 years old) of the Movimente Project in 2016/2017 composed the sample of the present study. This project was carried out in six public schools in the city of Florianópolis, Santa Catarina, Brazil. Test-retest reproducibility was assessed by the intraclass correlation coefficient and Gwet coefficient; internal consistency through McDonald's Omega; Hankins' Delta G coefficient verified the scale's discriminatory power and; confirmatory factor analysis to assess construct validity. RESULTS: Reproducibility values ranged from 0.71 to 0.78 for the dimensions (ICC), and ranged from 0.60 to 0.83 for the items (Gwet). McDonald's Ômega (0.82-0.91) for internal consistency measures. Discriminatory power ranging from 0.94 for the dimension Social Support and Friends to 0.98 for Psychological Well-Being. The factorial loads were > 0.40, except for item 19 (0.36). The fit quality indicators of the model were adequate (X2[df] = 1022.89 [311], p < 0.001; RMSEA = 0.053 (0.049-0.087); CFI = 0.988; TLI = 0.987), confirming the five-factor structure originally proposed. CONCLUSIONS: The Brazilian-version Kidscreen-27 achieved good levels of reproducibility, internal consistency, discriminatory power and construct validity. Its use is adequate to measure the health-related quality of life of adolescents in the Brazilian context.

Efforts on Changing Lifestyle Behaviors May Not Be Enough to Improve Health-Related Quality of Life Among Adolescents: A Cluster-Randomized Controlled Trial.

Schools have been the main context for physical activity (PA) and sedentary behavior (SB) interventions among adolescents, but there is inconsistent evidence on whether they also improve dimensions of the health-related quality of life (HRQoL). The aim of this study was to evaluate the effects of a school-based active lifestyle intervention on dimensions of HRQoL. A secondary aim was to verify whether sex, age, and HRQoL at baseline were moderators of the intervention effect. A cluster-randomized controlled trial was conducted at three control and three intervention schools in Florianopolis, Brazil. All students from 7th to 9th grade were invited to participate. A school year intervention, designed primarily to increase PA and reduce SB, included strategies focused on (i) teacher training on PA, SB, and nutrition, and availability of teaching materials related to these contents; (ii) environmental improvements (i.e., creation and revitalization of spaces for the practice of PA in school); and (iii) education strategies, with the availability of folders and posters regarding PA, SB, and nutrition. Participants and the research staffs were not blinded to group assignment, but a standardized evaluation protocol was applied at baseline and after the intervention (March and November 2017) using the KIDSCREEN-27 to assess HRQoL across five dimensions. Mixed linear models were performed to evaluate the effect of the Movimente intervention on the five HRQoL dimensions. Of the 921 students who answered the questionnaire at baseline, 300 and 434 completed the study in control and intervention groups, respectively (dropouts: 20%). The results revealed no significant effects of the intervention on any HRQoL dimensions. A reduction of the school environment dimension was observed in both the control (-2.44; 95% CI: -3.41 to -1.48) and intervention groups (-2.09; 95% CI: -2.89 to -1.30). Sensitivity analyses showed that students in the highest baseline tertiles of HRQoL in any dimension had a reduction in their respective scores from pre- to post-intervention in both school groups. In conclusion, our results demonstrated no intervention effect on HRQoL dimensions and those students with the highest levels of HRQoL at baseline on all dimensions reduced from pre to post-intervention. CLINICAL TRIAL REGISTRATION: The trial is registered at the Clinical Trial Registry (Trial ID: NCT02944318; date of registration: October 18, 2016).

Orientações para utilização de acelerômetros no Brasil / Instructions for accelerometer use in Brazil

O objetivo do presente estudo foi apresentar um conjunto de orientações para a utilização de acelerômetros no Brasil. O método consistiu na revisão e síntese de artigos que utilizaram acelerômetros como instrumento de medida objetiva da atividade física. Com base nesses estudos, buscou-se apresentar orientações para as fases pré-coleta (seleção do acelerômetro; testagem da calibração dos acelerômetros, atualização de firmware; estudo piloto; e definição de protocolo), coleta (distribuição dos acelerômetros; contato com participantes; e devolução dos acelerômetros) e pós-coleta (processamento; transformação e interpretação dos dados; e comparabilidade dos dados) do uso de acelerômetros. São descritos procedimentos para facilitar as tomadas de decisões relacionadas ao uso desses dispositivos, bem como para obtenção de dados de acelerometria válidos e reprodutíveis. As orientações são uma iniciativa de pesquisadores da área a fim de proporcionar um avanço metodológico nas medidas objetivas da atividade física. A adoção das orientações pode facilitar a padronização dos procedimentos empregados e a comparabilidade de resultados entre estudos com acelerômetros no Brasil.

The aim of this study was to develop instructions for using accelerometers to measure physical activity in Brazil. This manuscript is a review and synthesis of scientific papers that have used accelerometers for objective physical activity assessment in different age groups as well as studies providing directions for using activity monitors in large-scale studies. In this study, we present instructions for the pre-data collection (selection of monitor; unit calibration, firmware update, pilot study, protocol definition), data collection (monitor distribution, contacting participants, monitor return) and post-data collection (data processing, transformation and interpretation) phases. We describe procedures for facilitating decision making related to using accelerometers, as well as for obtaining valid and reliable accelerometer physical activity data. This set of instructions is an initiative of a group of physical activity researchers with the purpose of contributing to methodologically advance the field of objective physical activity measurement in Brazil. The current set of instructions intend to facilitate the standardization of procedures for collecting physical activity data with accelerometers in Brazil and, thus, for ascertaining future comparability of data collected in different studies.