Methodology and implementation of the WHO European Childhood Obesity Surveillance Initiative (COSI).

Establishment of the WHO European Childhood Obesity Surveillance Initiative (COSI) has resulted in a surveillance system which provides regular, reliable, timely, and accurate data on children's weight status-through standardized measurement of bodyweight and height-in the WHO European Region. Additional data on dietary intake, physical activity, sedentary behavior, family background, and school environments are collected in several countries. In total, 45 countries in the European Region have participated in COSI. The first five data collection rounds, between 2007 and 2021, yielded measured anthropometric data on over 1.3 million children. In COSI, data are collected according to a common protocol, using standardized instruments and procedures. The systematic collection and analysis of these data enables intercountry comparisons and reveals differences in the prevalence of childhood thinness, overweight, normal weight, and obesity between and within populations. Furthermore, it facilitates investigation of the relationship between overweight, obesity, and potential risk or protective factors and improves the understanding of the development of overweight and obesity in European primary-school children in order to support appropriate and effective policy responses.

Urban and rural differences in frequency of fruit, vegetable, and soft drink consumption among 6-9-year-old children from 19 countries from the WHO European region.

In order to address the paucity of evidence on the association between childhood eating habits and urbanization, this cross-sectional study describes urban-rural differences in frequency of fruit, vegetable, and soft drink consumption in 123,100 children aged 6-9 years from 19 countries participating in the fourth round (2015-2017) of the WHO European Childhood Obesity Surveillance Initiative (COSI). Children's parents/caregivers completed food-frequency questionnaires. A multivariate multilevel logistic regression analysis was performed and revealed wide variability among countries and within macroregions for all indicators. The percentage of children attending rural schools ranged from 3% in Turkey to 70% in Turkmenistan. The prevalence of less healthy eating habits was high, with between 30-80% and 30-90% children not eating fruit or vegetables daily, respectively, and up to 45% consuming soft drinks on >3 days a week. For less than one third of the countries, children attending rural schools had higher odds (OR-range: 1.1-2.1) for not eating fruit or vegetables daily or consuming soft drinks >3 days a week compared to children attending urban schools. For the remainder of the countries no significant associations were observed. Both population-based interventions and policy strategies are necessary to improve access to healthy foods and increase healthy eating behaviors among children.

Socioeconomic inequalities in overweight and obesity among 6- to 9-year-old children in 24 countries from the World Health Organization European region.

Childhood overweight and obesity have significant short- and long-term negative impacts on children's health and well-being. These challenges are unequally distributed according to socioeconomic status (SES); however, previous studies have often lacked standardized and objectively measured data across national contexts to assess these differences. This study provides a cross-sectional picture of the association between SES and childhood overweight and obesity, based on data from 123,487 children aged 6-9 years in 24 countries in the World Health Organization (WHO) European region. Overall, associations were found between overweight/obesity and the three SES indicators used (parental education, parental employment status, and family-perceived wealth). Our results showed an inverse relationship between the prevalence of childhood overweight/obesity and parental education in high-income countries, whereas the opposite relationship was observed in most of the middle-income countries. The same applied to family-perceived wealth, although parental employment status appeared to be less associated with overweight and obesity or not associated at all. This paper highlights the need for close attention to context when designing interventions, as the association between SES and childhood overweight and obesity varies by country economic development. Population-based interventions have an important role to play, but policies that target specific SES groups are also needed to address inequalities.