In more than half of pediatric instances, comorbid conditions coexisted with ADHD, and it was difficult to determine if the symptoms impairing function were caused by the comorbid condition or the underlying ADHD. In addition, comorbid illnesses raise the risk of a more severe and protracted course and make treatment choices more difficult. To enhance research on ADHD using biorepository and other electronic record data, it was crucial to creating an algorithm that recognized ADHD and comorbidities.