Jobling, Nina and Mjåland, Kristian and Clausen, Thomas and Heldal, Anne Taraldsen and Thylstrup, Birgitte and Vederhus, John-Kåre (2026) Medication transitions and predictors of illicit substance use during opioid agonist treatment: a three-year follow-up study. Addiction Science & Clinical Practice , 21 , (1) .