OBJECTIVES: This study examined (non-)monotonic time trends in psychological and somatic complaints among adolescents, along with gender differences. METHODS: Repeated cross-sectional Health Behaviour in School-aged Children (HBSC) data from 1994 to 2022 covering 15-year-old adolescents from 41 countries (N = 470,797) were analysed. Three polynomial logistic regression models (linear, quadratic, cubic) were tested for best fit, including separate analyses by gender and health complaints dimension. RESULTS: Time trend patterns varied by gender and health complaints dimension. Increases were found in 82.3% of cases (linear 25%, quadratic U-shaped 28.7%, cubic 28.7%), while 14% showed no clear trend, and 3.7% decreased. Boys typically showed linear increases or no clear trend over time, whereas girls generally showed cubic or U-shaped trends. Psychological complaints often displayed U-shaped or cubic patterns, whereas somatic complaints mostly showed linear increases. CONCLUSION: Psychological and somatic complaints demonstrated diverse time trend patterns across countries, with non-monotonic patterns (U-shaped and cubic) frequently observed alongside linear increases. These findings highlight the complexity of changes within countries over three decades, suggesting that linear modelling may not effectively capture this heterogeneity.

• Klíčová slova
• HBSC, adolescence, cross-national, gender differences, mental health,
• MeSH
• celosvětové zdraví MeSH
• lidé MeSH
• mladiství MeSH
• pacienti bez organického nálezu MeSH
• průřezové studie MeSH
• sexuální faktory MeSH
• somatoformní poruchy epidemiologie   MeSH
• zdraví dospívajících * trendy   MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

(1) Background: In Italy, the components of adolescents' mental well-being (psychological symptomatology and cognitive perception of life satisfaction) showed different temporal trends, suggesting the adoption of a multidimensional conceptualization. We aimed to assess temporal patterns and provide additional insights into Italian adolescents' mental well-being in the last decade by adopting the Dual Factor Model; (2) Methods: We used nationally representative samples of Italian students (n = 165,000) aged 11, 13, and 15 years across the three more recent Italian Health Behaviour in School-aged Children (HBSC) surveys. Two measures of mental well-being were used: life satisfaction (LS, indicator of positive subjective well-being) and psychological health complaints (PHC, indicator of mental illness); (3) Results: Our study showed that the overall sample has been moving from a Complete Mental Health (Flourishing) to an Incomplete Mental Illness (Struggling) condition. Among 13- and 15-year-old girls, a jump from one to the other mental condition was observed in the 2014-2018 and 2010-2014 time periods, respectively; (4) Conclusions: Our findings suggest that Italian adolescents, especially older girls, have been shifting from Complete Mental Health to Incomplete Mental Illness in the last decade. Further research is needed to investigate this breaking up of the connection between psychological symptomatology and cognitive perception of life satisfaction.

• Klíčová slova
• Dual Factor Model, HBSC, adolescents, gender, life satisfaction, mental health, mental well-being, psychological symptoms,
• Publikační typ
• časopisecké články MeSH