Low prevalence of relative age effects in Luxembourg's male and female youth football.

The relative age effect (RAE) is a well-established phenomenon in football. However, while the majority of previous studies focussed on established football nations, it remains unclear if the constraint of a limited population of soccer players in smaller countries associated with less strict selection procedures may reduce the risk of RAE. This study aims to investigate the RAE in Luxembourg that follows an 'open-door' selection policy in youth football due to the limited pool of players. Birthdates from all licensed and actively playing Luxembourgish youth footballers including all players of the youth national teams (396 girls and 10981 boys) competing in the season 2018/2019 were analysed and categorised into birth quarters and semesters. To further investigate a performance dependence of the RAE in amateur leagues, success was determined based on the teams' rankings at the end of the season. Differences between observed and expected birthdate distributions were calculated across all licensed players and age groups, within the national teams, and for the top- and bottom-tier football teams using chi-square statistics. While a RAE was absent across all age groups (except U7), significant RAEs with high effect sizes were observed in the top-level and national teams. These findings contrast the substantial RAE effects in large football nations and suggest that open selection systems might reflect an environmental constraint that limit the prevalence of RAE in football. Further, this study indicates that a performance dependence of the RAE is not limited to high level football but already occurs on an amateur level.

The Impact of the COVID-19 Lockdown on European Students' Negative Emotional Symptoms: A Systematic Review and Meta-Analysis.

Considerable changes to higher education approaches, as a response to the global coronavirus pandemic, has increased the stress on university students. The impact of these changes has had an effect on the negative emotional symptoms being experienced, which can lead to more severe mental health issues. The purpose of this meta-analysis was to determine the prevalence of anxiety, depression and stress during the coronavirus lockdown. A systematic review of three electronic databases (Google Scholar, PubMed and Medline) was conducted, with 13 studies from different European countries reporting data on students and their negative emotional symptoms identified. The random-effects model was used to perform the meta-analysis on anxiety, depression and stress. The overall pooled prevalence rate was 55% (95% CI: 45-64%) for anxiety, 63% (95% CI: 52-73%) for depression and 62% (95% CI: 43-79%) for stress. The impact of the coronavirus pandemic on negative emotional symptoms has been serious with studies reporting high prevalence rates for these. Isolation, reduced social contact, duration of quarantine and restrictions, which are the characteristics of a lockdown, played an important role in increased negative emotional symptoms for students. Countries have to be aware of this situation and develop mental support strategies to mitigate the impact.