2.1. Study Design and Population
sedentary behaviors, weight reduction
This study is part of a community trial whose main purpose was to evaluate the effect of a multi-component educational intervention aimed at schoolchildren and their parents. The intervention consisted of promoting healthy eating habits, increased physical activity, and decreased time spent in sedentary behavior in schoolchildren. The design and implementation of the intervention have been previously described [Four primary schools located in the center of Mexico City with similar number of students were included in the study; two were public schools and two were private. One public and one private school were assigned to the intervention group (IG), and one public and one private school were assigned to the control group (CG). Schoolchildren in grades 1 through 4 (6 to 10 years) and their parents were asked to participate in the study. Before the study implementation, educational materials and the website were designed and developed, which were the tools of the intervention. Prior to beginning the study, the objectives of the study, procedures, and measurements to be carried out during the study’s one-year duration were explained to the parents, children, and teachers. Parents and children signed an informed consent and an assent agreeing to participate in the study, respectively. Boys and girls were included, regardless of their z-score for body mass index (BMI). Children who were participating in a weight reduction program were excluded. Participants who did not answer the baseline questionnaire on PA and sedentary behaviors were removed from the analysis. The study was approved by the Ethics, Research, and Biosafety Committees of the Federico Gómez Children’s Hospital of Mexico. Additionally, the Ministry of Public Education and directors of the participating schools authorized the study.