Estudio multi-céntrico SAYCARE, de evaluación del estado nutricional y estilos de vida en niños y adolescentes

SAYCARE multicenter study: Design, harmonization process, cultural adaptation and quality control

Luís Alberto Moreno1,2, Augusto Cesar F. De Moraes2, Tara Rendo-Urteaga2, Laura Inés Gonzalez-Zapata2, Heráclito Barbosa Carvalho3

1 YCARE (Youth/Child and Cardiovascular Risk and Environmental). The University of Sao Paulo, Sao Paulo, Brasil. 2 GENUD (Growth, Exercise, NUtrition and Development Research Group), Faculty of Health Sciences, University of Zaragoza-CITA, Zaragoza, España. 3 School of Nutrition and Dietetics, University of Antioquia, Medellin, Colombia

Introduction: Several lifestyle variables are associated with obesity 1, and cardiovascular disease 2, however, these behaviors are complex and vary by age, sex, seasonality, time of day and day of the week. Moreover, they are influenced by biological, sociological, psychological and environmental factors 3. In epidemiological studies, the methods used to obtain these data must be reliable, validated in the study population and, if possible, allowing comparisons between countries. Multicenter studies that use standardized methods appears as the best strategy to establish allows comparisons between countries, such as those developed in Europe about lifestyle and cardiovascular health in children and adolescents4. From this point of view, to develop methods in South America, it is important to maximize the data collection quality and thus to try to understand differences between these factors among countries. The aims are: (i) To develop valid and reliable measurement methods to obtain information on: social and environmental factors, family environment, food intake, preferences and food choices, physical activity and sedentary behaviors, body composition, oral health, lipids and cardiovascular health biomarkers; (ii) To assess the reliability of these methods (iii) To assess the validity of these methods. Methods: This is a multicenter pilot study, entitled South American Youth/Child cARdiovascular and Environment Study (acronym: SAYCARE Study), that was held in seven South American cities: São Paulo and Teresina (Brazil), Buenos Aires (Argentina), Santiago (Chile), Montevideo (Uruguay), Lima (Peru) and Medellin (Colombia). The study assessed pre-school, primary school, and up to the third year of high school subjects (3 to 17 years), enrolled in both public and private schools of their respective cities. The sample size was estimated based on the experience of other multicenter projects, in which a feasibility pilot study was previously conducted, and the reliability and validity of the used method was evaluated4, 5. The sample consists of 100 participants in each age-range (pre-school, primary school and high school) for each research center. Losses and SIMPOSIOS rejections up to 10% are expected, so 120 participants will be invited for each age range, for a total of 360 children and adolescents for each research center and 2,520 subjects in total. Public and a private school will be selected in each city for each age range. Children and adolescents will be selected in each city randomly, based on the enrolled school’s student lists, resulting in at least 50% of participants for each sex. The Research Ethics Committee of each city involved this study approved the protocol. The field workers were harmonized for all the relevant measurements by training program at least 40 hours to obtain the qualifications required for conducting fieldwork. A detailed protocol of all the research procedures was produced and study design and instruments were standardized. The field workers training consisted of both two: theoretical and practical sessions. Triplicate measurements were made in 10 children/adolescents per researcher, simulating the fieldwork. These previous sessions included the final versions of the questionnaires, anthropometry, blood pressure, logistics of the fieldwork and evaluation of the interviewers’ work. The questionnaires apply twice to assess the reliability of instruments comparing two measures of the instrument in the same subject. The validity of a measure is the ability of an instrument to correctly classify research subjects; this will be assessed comparing subjective measures with objective measures. The agreement between measurements will be calculated by determining the kappa coefficients for categorical variables and intraclass correlation coefficients for quantitative variables, which will be complemented by the development of Bland-Altman. The correlation will be calculated by Spearman and Pearson correlation coefficients for nonparametric and parametric variables respectively. Conclusion: We develop a research protocol allowing develop a pilot multicenter cross-sectional study aiming to assess the nutritional status, lifestyle behaviors and cardiometabolic risk factor in South American children and adolescents. References: 1. De Moraes AC, Fadoni RP, Ricardi LM, Souza TC, Rosaneli CF, Nakashima AT, et al. Prevalence of abdominal obesity in adolescents: a systematic review. Obes Rev 2011;12(2):69-77. 2. de Moraes AC, Carvalho HB, Rey-López JP, Gracia-Marco L, Beghin L, Kafatos A, et al. Independent and combined effects of physical activity and sedentary behavior on blood pressure in adolescents: gender differences in two cross-sectional studies. PLoS One. 2013;8(5):e62006. 3.Egger G, Swinburn B. An ‘ecological’ approach to the obesity pandemic. BMJ. 1997;315(7106):477-480. 4. Moreno LA, De Henauw S, González-Gross M, Kersting M, Molnár D, Gottrand F, et al. Design and implementation of the Healthy Lifestyle in Europe by Nutrition in Adolescence Cross-Sectional Study. Int J Obes (Lond). 2008;32 Suppl 5:S4-11. 5.Ahrens W, Bammann K, Siani A, Buchecker K, De Henauw S, Iacoviello L, et al. The IDEFICS cohort: design, characteristics and participation in the baseline survey. Int J Obes (Lond). 2011;35 Suppl 1:S3-15.