A Cross-Cultural Comparative Study on Italian and American University Students’ Psychological Symptoms and the Predicting Role of Personality Traits

(1) Background: This study aimed to compare psychological symptoms between Italian university students and American college students, considering both external (e.g., nationality) and internal variables (e.g., gender, age, and personality traits) potentially associated with mental health status. (2) Methods: A total of 201 Italian students from the University of Parma and 214 American students from Boston College were recruited. Participants completed the Symptom Questionnaire (SQ) and the 16 Personality Factors Questionnaire (16PF). Group comparisons were conducted on socio-demographic and psychological variables using chi-square and independent samples <i>t</i>-tests. Subsequently, hierarchical linear regression analyses were performed separately for each sample to identify personality traits that predict psychological symptoms, while controlling for gender and age. (3) Results: Both samples scored above the clinical cut-off on all SQ symptom scales. American students reported significantly higher levels of depression and hostility. Across both groups, psychological distress was primarily predicted by high tension and low emotional stability, with personality traits explaining a greater proportion of variance than nationality. Traits related to social interaction and emotional regulation also emerged as significant predictors. (4) Conclusions: Identifying personality profiles that are more vulnerable to psychological symptoms may support the development of early identification strategies and targeted prevention programs in university settings.