Behavioral and Psychosocial Correlates of Gender Differences in Adolescent Mental Health: A Regional Cross-Sectional Study in Northern Italy

Background: Gender differences in adolescent mental health are well documented; however, the extent to which modifiable behavioral and psychosocial factors account for the excess of mental health problems in females remains insufficiently quantified. Methods: Data from the 2025 Corona and Psyche South Tyrol (COP-S) survey comprised a base sample of 2428 adolescents aged 11–19 years (51.4% males) with valid self-reported data. Multivariable regression analyses were conducted on 1448–1603 adolescents (depending on the outcome) who provided complete responses to the relevant predictor and outcome measures. Gender differences in depressive symptom scores (PHQ-2), generalized anxiety symptom scores (SCARED-GAD), and emotional/behavioral difficulties (SDQ) were examined using Mann–Whitney U and chi-square tests. Multivariable linear regression models were used to assess the associations between mental health outcomes and the ten predictors. Gender effects were quantified by comparing standardized regression coefficients from unadjusted and adjusted models. Results: Female adolescents reported higher generalized anxiety symptoms (median 6 vs. 4; rank-biserial r = 0.24), depressive symptoms (r = 0.13), and emotional/behavioral (r = 0.08) scores than male adolescents. School stress, problematic Internet use, and sleep-onset difficulties were the factors most strongly associated with all three outcomes (all p < 0.001). After multivariable adjustment, gender remained significantly associated with generalized anxiety symptoms (β = 0.18) and depressive scores (β = 0.09) but no longer reached significance for emotional/behavioral scores (β = 0.04, p = 0.078). The attenuation of the gender effect ranged from 25.3% for generalized anxiety symptoms to 37.1% for depressive symptoms and 58.5% for emotional/behavioral difficulties. Conclusions: Gender differences in adolescent mental health were substantially attenuated after adjustment for modifiable behavioral and psychosocial factors, with the gender difference in emotional/behavioral scores no longer statistically significant after adjustment. Persistent gender disparities in generalized anxiety symptoms suggest that mechanisms beyond the measured behavioral correlates may contribute to this gender difference and warrant further investigation.