• Causal modelling of variation in clinical practice and long-term outcomes of ADHD using Norwegian registry data: The ADHD controversy project 

      Mykletun, Arnstein; Widding-Havneraas, Tarjei; Chaulagain, Ashmita; Lyhmann, Ingvild; Bjelland, Ingvar; Halmøy, Anne; Elwert, Felix; Butterworth, Peter; Markussen, Simen; Zachrisson, Henrik Daae; Rypdal, Knut (Journal article; Peer reviewed, 2021)
      Introduction Attention-deficit/hyperactivity disorder (ADHD) is among the most common mental disorders in children and adolescents, and it is a strong risk factor for several adverse psychosocial outcomes over the lifespan. ...
    • Effect of ADHD medication on risk of injuries: a preference-based instrumental variable analysis 

      Widding-Havnerås, Tarjei; Elwert, Felix; Markussen, Simen; Zachrisson, Henrik Daae; Lyhmann, Ingvild; Chaulagain, Ashmita; Bjelland, Ingvar; Halmøy, Anne; Rypdal, Knut; Mykletun, Arnstein (Journal article; Peer reviewed, 2023)
      ADHD is associated with an increased risk of injury. Causal evidence for effects of pharmacological treatment on injuries is scarce. We estimated effects of ADHD medication on injuries using variation in provider preference ...
    • Effect of Pharmacological Treatment of Attention-Deficit/Hyperactivity Disorder on Criminality 

      Widding-Havnerås, Tarjei; Zachrisson, Henrik Daae; Markussen, Simen; Elwert, Felix; Lyhmann, Ingvild; Chaulagain, Ashmita; Bjelland, Ingvar; Halmøy, Anne; Rypdal, Knut; Mykletun, Arnstein (Journal article; Peer reviewed, 2023)
      Objective: Criminality rates are higher among persons with attention-deficit/hyperactivity disorder (ADHD), and evidence that medication reduces crime is limited. Medication rates between clinics vary widely even within ...
    • Geographical variation in ADHD: do diagnoses refect symptom levels? 

      Widding-Havneraas, Tarjei; Markussen, Simen; Elwert, Felix; Lyhmann, Ingvild; Bjelland, Ingvar; Halmøy, Anne; Chaulagain, Ashmita; Ystrøm, Eivind; Mykletun, Arnstein; Zachrisson, Henrik Daae (Journal article; Peer reviewed, 2023)
      Rates of ADHD diagnosis vary across regions in many countries. However, no prior study has investigated how much within-country geographic variation in ADHD diagnoses is explained by variation in ADHD symptom levels. We ...
    • Preference-based instrumental variables in health research rely on important and underreported assumptions: a systematic review 

      Widding-Havneraas, Tarjei; Chaulagain, Ashmita; Lyhmann, Ingvild; Zachrisson, Henrik Daae; Elwert, Felix; Markussen, Simen; McDaid, David; Mykletun, Arnstein (Journal article; Peer reviewed, 2021)
      Objective: Preference-based instrumental variables (PP IV) designs can identify causal effects when patients receive treatment due to variation in providers’ treatment preference. We offer a systematic review and methodological ...
    • A systematic meta-review of systematic reviews on attention deficit hyperactivity disorder 

      Chaulagain, Ashmita; Lyhmann, Ingvild; Halmøy, Anne; Widding-Havnerås, Tarjei; Nyttingnes, Olav; Bjelland, Ingvar; Mykletun, Arnstein (Journal article; Peer reviewed, 2023)
      Background There are now hundreds of systematic reviews on attention deficit hyperactivity disorder (ADHD) of variable quality. To help navigate this literature, we have reviewed systematic reviews on any topic on ...
    • Variation in attitudes toward diagnosis and medication of ADHD: a survey among clinicians in the Norwegian child and adolescent mental health services 

      Lyhmann, Ingvild; Widding-Havnerås, Tarjei; Zachrisson, Henrik Daae; Bjelland, Ingvar; Chaulagain, Ashmita; Mykletun, Arnstein; Halmøy, Anne (Journal article; Peer reviewed, 2022)
      Prevalence and medication rates of ADHD vary geographically, both between and within countries. No absolute cutoff exists between ADHD and normal behavior, making clinician attitudes (leading to local practice cultures) a ...