Cross-National Study on the Convergent, Discriminant, and Concurrent Validity of the "Body Size Perception" Item in the Health Behaviour in School-aged Children Survey.

Background: Despite its significant usefulness in adolescent health studies, the single-item "body size perception" question, developed within the Health Behaviour in School-aged Children (HBSC) survey, has yet to undergo multidimensional validation.

Objectives: To assess the convergent, divergent and concurrent validity of the HBSC body size perception question among adolescents.

Methods: The single-item HBSC body size perception question is as follows: "Do you think your body is…?," with answers ranging from "much too thin" to "much too fat.

Weekday sleep duration and morning tiredness are independent covariates of breakfast skipping in adolescents.

Background/objectives: Although regular breakfast consumption is associated with various health benefits, many adolescents skip this meal, particularly those with shorter sleep durations. In order to better understand the association between sleep duration and breakfast consumption among youth, we analyzed the association between weekday morning tiredness and daily breakfast consumption in adolescents, and explored the mediating role of morning tiredness in the association between sleep duration and daily breakfast consumption on weekdays.

Subjects/methods: The "Health Behaviour in School-aged Children" survey conducted in 2018 in French-speaking Belgian schools provided data (n = 8444 11-20-year-old adolescents) on bed- and wake-up times, and on the frequency of breakfast consumption and morning tiredness on weekdays.

Long-term trends in the consumption of sugary and diet soft drinks among adolescents: a cross-national survey in 21 European countries.

Purpose: To assess country-level trends in the prevalence of daily consumption of sugary (2002-2018) and diet (2006-2018) soft drinks among European adolescents, overall and by family material affluence.

Methods: We used 2002, 2006, 2010, 2014 and 2018 data from the 'Health Behaviour in School-aged Children' survey. Nationally representative samples of adolescents completed a standardised questionnaire at school, including a short food frequency questionnaire (n = 530,976 and 21 countries for sugary soft drinks; n = 61,487 and 4 countries for diet soft drinks).

Dietary disparities among adolescents according to individual and school socioeconomic status: a multilevel analysis.

This study aimed to estimate disparities in dietary habits according to the individual and contextual socioeconomic status (SES), while taking into account school nutrition-related characteristics. Data came from the 2018 cross-sectional "Health Behaviour in School-aged Children" (HBSC) survey. Multilevel multiple logistic regressions were performed.