Handwriting assessment to distinguish comorbid learning difficulties from attention deficit hyperactivity disorder in Chinese adolescents: A case-control study

Objectives: Attention deficit hyperactivity disorder (ADHD) and learning difficulties (LDs) are proposed as 2 overlapping disorders. The objective of this study was to investigate the handwriting performance in ADHD and comorbid ADHD-LD adolescents. Methods: The study examined the Chinese and English handwriting performance and sensorimotor skills of 32 ADHD, 12 ADHD-LD, and their matched controls. Results: Participants with ADHD had comparable writing time and speed, but the readability was lower than their controls. Participants with ADHD-LD had lower writing speeds in both Chinese and English handwriting than their controls. The ADHD and ADHD-LD groups also showed larger variations in either speed or pen pressure than their controls. Chinese handwriting assessment effectively classified ADHD and ADHD-LD with good sensitivity and positive predictive value. Conclusions: Clinicians should be aware of the fundamental difference between the 2 disorders and make good use of handwriting assessment as a reference to deliver effective therapies and trainings.