Chronic pain co-occurrence is common during adolescence across countries, the prevalence being among girls and in older age groups. Significant cross-country variations in the chronic pain prevalence and chronic pain patterns among adolescents exist. Significant country differences emerge for specific chronic pain patterns in association with adolescent demographics.

Insufficient and poor sleep patterns are common among adolescents worldwide. Up to now, the evidence on adolescent sleep has been mostly informed by country-specific studies that used different measures and age groups, making direct comparisons difficult. Cross-national data on adolescent sleep that could inform nations and international discussions are lacking. We examined the sleep patterns of adolescents across 24 countries and by gender, age, and affluence groups. Methods: We obtained sleep data on 165,793 adolescents (mean age 13.5 years; 50.5% girls) in 24 European and North American countries from the recent cross-sectional Health Behaviour in School-aged Children surveys (2013e2014 and 2017e2018). For each country, we calculated the age-standardized mean in sleep duration, timing, and consistency and the proportions meeting IMPLICATIONS AND CONTRIBUTION Conflicts of interest: The authors have no conflicts of interest to disclose. Disclosure: This supplement was supported by the World Health Organization European Office and the University of Glasgow. The articles have been peerreviewed and edited by the editorial staff of the Journal of Adolescent Health. The opinions or views expressed in this supplement are those of the authors and do not necessarily represent the official position of the funder.

The findings indicated that adolescents who report more frequent recurrent health complaints are also more likely to report more frequent medicine use for their health complaints. Adolescent boys with weekly health complaints have the same risk of medicine use as girls with weekly health complaints. The importance of educating school-aged children to interpret their bodily feelings and complaints and to use medicines appropriately is of high priority.

Recurrent pain in adolescence is common cross-nationally. Adolescents with recurrent pain are more likely to use medicine in general. Recurrent pain and medicine use should be addressed in adolescent health policies.

BackgroundYoung individuals are the age group with the highest risk of car accidents. One of main explanations relies on the use of psychoactive substances (alcohol, illegal and medicinal drugs), which are known to be major risk factors of road accidents, and whose consumption is almost universally more common among younger drivers. Although the correlation between psychoactive substances use and decrease in driving performance has been established in controlled experimental or laboratory settings, few studies were conducted in naturalistic circumstances. The TEND by Night project has been designed to evaluate the relationship between driving performance and psychoactive substances assumption in young drivers enrolled at typical places of consumption.Methods/DesignThe TEND by Night project, endorsed by the European Commission, is a multidisciplinary, multi-centric, cross-sectional study conducted in six European countries (Italy, Belgium/Netherlands, Bulgaria, Spain, Poland and Latvia). The study population consists of 5000 young drivers aged 16-34 years, attending recreational sites during weekend nights. The intervention is based on the portal survey technique and includes several steps at the entrance and exit of selected sites, including the administration of semi-structured questionnaires, breath alcohol test, several drug assumption test, and measurement of the reaction time using a driving simulator. The main outcome is the difference in reaction time between the entrance and exit of the recreation site, and its correlation with psychoactive substances use. As a secondary outcome it will be explored the relationship between reaction time difference and the amount of consumption of each substance. All analyses will be multivariate.DiscussionThe project methodology should provide some relevant advantages over traditional survey systems. The main strengths of the study include the large and multicentric sample, the objective measurement of substance assumption (which is typically self-reported), the application of a portal survey technique and the simultaneous evaluation of several psychoactive substances.