Healthcare Service Use Before ADHD Diagnosis: Population-Based Case-Control Study

This population-based study compared healthcare service utilization in 8,127 children/young people with ADHD and 40,136 matched controls using English primary care records (1998-2015), finding that those later diagnosed with ADHD attended healthcare services twice as frequently in the 2 years before diagnosis. ADHD cases showed strongest associations with mental/behavioral disorder visits (25-fold higher) but also elevated attendance for common conditions like ENT issues, asthma, and eczema.