Attention-deficit/hyperactivity disorder (ADHD) symptoms and their relation to diagnosed ADHD, sociodemographic characteristics, and substance use among patients receiving opioid agonist therapy: a Norwegian cohort study. - Vold JH; Halmøy A; Chalabianloo F; Pierron MC; Løberg EM; Johansson KA; Fadnes LT (BMC psychiatry, 2023)