Associations Among Developmental Coordination Disorder Traits, Neurodevelopmental Difficulties and University Personality Inventory Scores in Undergraduate Students at a Japanese National University: A Cross-Sectional Correlational Study

Background/Objectives: Developmental coordination disorder (DCD) commonly co-occurs with attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and specific learning disorder (SLD), affecting academics, mental health, and lifestyle. Although screeners such as the Adolescents and Adults Coordination Questionnaire (AAC-Q) are widely used elsewhere, recognition and support for DCD in Japan remain limited. This study examined associations among DCD traits, ADHD/ASD-related difficulties, learning difficulties, mental health difficulties, and lifestyle factors in university students. Methods: We conducted a web-based survey of 16,295 students; responses from 527 were analyzed. The instruments used for the analysis included the AAC-Q, short forms of ADHD and ASD Difficulty Scales, the 7-item Learning Difficulty Scale for Postsecondary Students and 10-item Scale for Childhood Learning Difficulties, and the University Personality Inventory (UPI). Nonparametric and Spearman’s rank correlations were performed. Results: DCD traits were observed at 7.4% (AAC-Q ≥ 32). This is a screen-positive proportion only. AAC-Q scores correlated strongly with ADHD difficulties (r = 0.65), moderately to strongly with ASD difficulties (r = 0.55), and moderately with mental health difficulties measured by the UPI (r = 0.41). Conclusions: These findings suggest that identifying DCD traits at university entry may be associated with greater student self-understanding and improved access to appropriate support. They support targeted DCD screening alongside ADHD/ASD screening at university entry, rather than universal screening.