Fagområder
Psykiatri, registerforskning, epidemiologi, klinisk forskning, hjerneavbildning
Faglig bakgrunn
Lege, psykiater, ph.d.
Prosjekter og publikasjoner
- Ingibjörg Magnúsdóttir, Anikó Lovik, Anna Bára Unnarsdóttir, Daniel L. McCartney, Helga Ask, Kadri Kõiv, Lea Arregui Nordahl Christoffersen, Sverre Urnes Johnson, Arna Hauksdóttir, Chloe Fawns-Ritchie, Dorte Helenius, Li Lu, Omid Vakili Ebrahimi, Asle Hoffart, David J Porteous, Fang Fang, Johanna Jakobsdottir, Kelli Lehto, Ole Andreassen, Ole Pedersen, Thor Aspelund, Unnur Anna Valdimarsdottir, Lill-Iren Schou Trogstad, Ragnar Nesvåg, Per Minor Magnus, (2022). Acute COVID-19 severity and mental health morbidity trajectories in patient populations of six nations: an observational study. The Lancet Public Health doi: 10.1016/S2468-2667(22)00042-1
- Martin Steen Tesli, Eirik Magnus Meek Degerud, Oleguer Plana-Ripoll, Kristin Gustavson, Fartein Ask Torvik, Eivind Ystrøm, Helga Ask, Natalia Tesli, Anne Høye, Camilla Stoltenberg, Ted Reichborn-Kjennerud, Ragnar Nesvåg, Øyvind Erik Næss, Acta Psychiatrica Scandinavica s. 481-493. doi: 10.1111/acps.13407
- Ingvild Odsbu, Marte Handal, Vidar Hjellvik, Petter Chr. Borchgrevink, Thomas Clausen, Ragnar Nesvåg, Svetlana Ondrasova Skurtveit, (2022). Vedvarende bruk av opioider og samtidig bruk av andre vanedannende legemidler. Tidsskrift for Den norske legeforening doi: 10.4045/tidsskr.21.0659
- Anna Bára Unnarsdóttir, Anikó Lovik, Chloe Fawns-Ritchie, Helga Ask, Kadri Kõiv, Kristen Hagen, Maria Didriksen, Lea Arregui Nordahl Christoffersen, Alexander Berg Garðarsson, Andrew McIntosh, Anna K. Kähler, Archie Campbell, Arna Hauksdóttir, Christian Erikstrup, Dorte Helenius Mikkelsen, Drew Altschul, Edda Bjork Thordardottir, Emma Maria Frans, Gerd Kvale, Gunnar Tómasson, Hanna Maria Kariis, Harpa Lind Jónsdóttir, Harpa Rúnarsdóttir, Ingibjörg Magnúsdóttir, Jarle Eid, Jóhanna Jakobsdóttir, Kaspar René Nielsen, Kathrine Agergård Kaspersen, Lili Milani, Lill-Iren Schou Trogstad, Lu Yi, Mie Topholm Bruun, Patrick F. Sullivan, Per Minor Magnus, Qing Shen, Ragnar Nesvåg, Ragnhild Eek Brandlistuen, Reedik Mägi, Sisse Rye Ostrowski, Solveig Løkhammer, Stian Solem, Ted Reichborn-Kjennerud, Thomas Folkmann Hansen, Thomas Werge, Thor Aspelund, David J. Porteous, Fang Fang, Kelli Lehto, Ole Andreassen, Ole Birger Vesterager Pedersen, Stephanie Francoise Claire Le Hellard, Unnur Anna Valdimarsdóttir, (2021). Cohort Profile: COVIDMENT: COVID-19 cohorts on mental health across six nations. International Journal of Epidemiology s. 1-15. doi: 10.1093/ije/dyab234
- Ingvild Odsbu, Marte Handal, Vidar Hjellvik, Petter Chr. Borchgrevink, Thomas Clausen, Aleksi Hamina, Torgeir Gilje Lid, Ragnar Nesvåg, Svetlana Ondrasova Skurtveit, (2021). Bruk av andre vanedannende legemidler blant opioidbrukere med langvarige smerter. Norsk Epidemiologi s. 45-53. doi: 10.5324/nje.v29i1-2.4045
- Anne Høye, Bjarne K. Jacobsen, Jørgen Gustav Bramness, Ragnar Nesvåg, Ted Reichborn-Kjennerud, Ina Heidi Heiberg, (2021). Total and cause‑specific mortality in patients with personality disorders: the association between comorbid severe mental illness and substance use disorders. Social Psychiatry and Psychiatric Epidemiology s. 1809-1819. doi: 10.1007/s00127-021-02055-3
- Ina Heidi Heiberg, Ragnar Nesvåg, Lise Balteskard, Jørgen Gustav Bramness, Christina M. Hultman, Øyvind Næss, Ted Reichborn-Kjennerud, Eivind Ystrøm, Bjarne K. Jacobsen, Anne Høye, (2020). Diagnostic tests and treatment procedures performed prior to cardiovascular death in individuals with severe mental illness. Acta Psychiatrica Scandinavica s. 439-451. doi: 10.1111/acps.13157
- Ina Heidi Heiberg, Bjarne K. Jacobsen, Lise Balteskard, Jørgen Gustav Bramness, Øyvind Næss, Eivind Ystrøm, Ted Reichborn-Kjennerud, Christina M. Hultman, Ragnar Nesvåg, Anne Høye, (2019). Undiagnosed cardiovascular disease prior to cardiovascular death in individuals with severe mental illness. Acta Psychiatrica Scandinavica s. 558-571. doi: 10.1111/acps.13017
- Ingrid Dieset, Ragni Helene Mørch, Sigrun Hope, Eva Zsuzsanna Hoseth, Elina Johanna Reponen, Jon Michael Gran, Monica Aas, Annika Michelsen, Ted Reichborn-Kjennerud, Ragnar Nesvåg, Ingrid Agartz, Ingrid Melle, Pål Aukrust, Srdjan Djurovic, Torill Ueland, Ole Andreas Andreassen, (2018). An association between YKL-40 and type 2 diabetes in psychotic disorders. Acta Psychiatrica Scandinavica s. 37-45. doi: 10.1111/acps.12971
- Lynn Mørch-Johnsen, Stener Nerland, Kjetil Nordbø Jørgensen, Kåre Osnes, Cecilie Bhandari Hartberg, Ole Andreas Andreassen, Ingrid Melle, Ragnar Nesvåg, Ingrid Agartz, (2018). Cortical thickness abnormalities in bipolar disorder patients with a lifetime history of auditory hallucinations. Bipolar Disorders s. 647-657. doi: 10.1111/bdi.12627
- Ina Heidi Heiberg, Bjarne K. Jacobsen, Ragnar Nesvåg, Jørgen Gustav Bramness, Ted Reichborn-Kjennerud, Øyvind Næss, Eivind Ystrøm, Christina M. Hultman, Anne Høye, (2018). Total and cause-specific standardized mortality ratios in patients with schizophrenia and/or substance use disorder. PLOS ONE doi: 10.1371/journal.pone.0202028
- Ragnar Nesvåg, Jørgen Gustav Bramness, Marte Handal, Ingeborg Hartz, Vidar Hjellvik, Svetlana Skurtveit, (2018). The incidence, psychiatric co-morbidity and pharmacological treatment of severe mental disorders in children and adolescents. European psychiatry s. 16-22. doi: 10.1016/j.eurpsy.2017.12.009
- Nathan A. Gillespie, Steven H. Aggen, Amanda E. Gentry, Michael Churton Neale, Gun Peggy S. Knudsen, Robert Frederick Krueger, Susan Carol South, Nikolai Olavi Czajkowski, Ragnar Nesvåg, Eivind Ystrøm, Tom Henrik Rosenström, Fartein Ask Torvik, Ted Reichborn-Kjennerud, Kenneth Seedman Kendler, (2018). Testing Genetic and Environmental Associations Between Personality Disorders and Cocaine Use: A Population-Based Twin Study. Twin Research and Human Genetics s. 24-32. doi: 10.1017/thg.2017.73
- Nathan A. Gillespie, Steven H. Aggen, Michael C. Neale, Gun Peggy S. Knudsen, Robert F. Krueger, Susan C. South, Nikolai Olavi Czajkowski, Ragnar Nesvåg, Eivind Ystrøm, Kenneth S. Kendler, Ted Reichborn-Kjennerud, (2018). Associations between personality disorders and cannabis use and cannabis use disorder: a population‐based twin study. Addiction s. 1488-1498. doi: 10.1111/add.14209
- Svetlana Skurtveit, Jørgen Gustav Bramness, Vidar Hjellvik, Ingeborg Hartz, Ragnar Nesvåg, Lars Johan Hauge, Marte Handal, (2018). Increase in diagnosis of depressive disorders contributes to the increase in antidepressant use in adolescents. Acta Psychiatrica Scandinavica s. 413-421. doi: 10.1111/acps.12877
- Kristin Gustavson, Ann Kristin Knudsen, Ragnar Nesvåg, Gun Peggy S. Knudsen, Stein Emil Vollset, Ted Reichborn-Kjennerud, (2018). Prevalence and stability of mental disorders among young adults: Findings from a longitudinal study. BMC Psychiatry doi: 10.1186/s12888-018-1647-5
- Elizabeth C. Long, Steven H. Aggen, Michael Churton Neale, Gun Peggy Knudsen, Robert Frederick Krueger, Susan Carol South, Nikolai Olavi Czajkowski, Ragnar Nesvåg, Eivind Ystrøm, Fartein Ask Torvik, Kenneth Seedman Kendler, Nathan A. Gillespie, Ted Reichborn-Kjennerud, (2017). The association between personality disorders with alcohol use and misuse: A population-based twin study. Drug and Alcohol Dependence s. 171-180. doi: 10.1016/j.drugalcdep.2017.01.022
- Ragnar Nesvåg, Erik Gunnar Jönsson, Inger Johanne Bakken, Gun Peggy Knudsen, Thomas Bjella, Ted Reichborn-Kjennerud, Ingrid Melle, Ole Andreas Andreassen, (2017). The quality of severe mental disorder diagnoses in a national health registry as compared to research diagnoses based on structured interview. BMC Psychiatry doi: 10.1186/s12888-017-1256-8
- Kjetil Nordbø Jørgensen, Ragnar Nesvåg, Stener Nerland, Lynn Mørch-Johnsen, Lars Tjelta Westlye, Elisabeth Lange, Unn Kristin H. Haukvik, Cecilie Bhandari Hartberg, Ingrid Melle, Ole Andreas Andreassen, Ingrid Agartz, (2017). Brain volume change in first-episode psychosis: an effect of antipsychotic medication independent of BMI change. Acta Psychiatrica Scandinavica s. 117-126. doi: 10.1111/acps.12677
- Elisabeth Lange, Stener Nerland, Kjetil Nordbø Jørgensen, Lynn Mørch-Johnsen, Ragnar Nesvåg, Cecilie Bhandari Hartberg, Unn Kristin H. Haukvik, Kåre Osnes, Ingrid Melle, Ole Andreas Andreassen, Ingrid Agartz, (2017). Alcohol use is associated with thinner cerebral cortex and larger ventricles in schizophrenia, bipolar disorder and healthy controls. Psychological Medicine s. 655-668. doi: 10.1017/S0033291716002920
- Ragnar Nesvåg, Ted Reichborn-Kjennerud, Nathan Gillespie, Gun Peggy Knudsen, Jørgen Gustav Bramness, Kenneth S Kendler, Eivind Ystrøm, (2017). Genetic and Environmental Contributions to the Association Between Cannabis Use and Psychotic-Like Experiences in Young Adult Twins. Schizophrenia Bulletin s. 644-653. doi: 10.1093/schbul/sbw101
- Lynn Mørch-Johnsen, Ragnar Nesvåg, Kjetil Nordbø Jørgensen, Elisabeth Lange, Cecilie Bhandari Hartberg, Unn Kristin H. Haukvik, Kristiina Kompus, Rene Westerhausen, Kåre Osnes, Ole Andreas Andreassen, Ingrid Melle, Kenneth Hugdahl, Ingrid Agartz, (2016). Auditory cortex characteristics in schizophrenia: Associations with auditory hallucinations. Schizophrenia Bulletin s. 75-83. doi: 10.1093/schbul/sbw130
- Petter Andreas Ringen, Ragnar Nesvåg, Siri Helle, Trine Vik Lagerberg, Elisabeth Lange, Else-Marie Løberg, Ingrid Agartz, Ole Andreas Andreassen, Ingrid Melle, (2016). Premorbid cannabis use is associated with more symptoms and poorer functioning in schizophrenia spectrum disorder. Psychological Medicine s. 3127-3136. doi: 10.1017/S0033291716001999
- Ragnar Nesvåg, Ingeborg Hartz, Jørgen Gustav Bramness, Vidar Hjellvik, Marte Handal, Svetlana Skurtveit, (2016). Mental disorder diagnoses among children and adolescents who use antipsychotic drugs. European Neuropsychopharmacology s. 1412-1418. doi: 10.1016/j.euroneuro.2016.07.001
- Ingeborg Hartz, Svetlana Skurtveit, Vidar Hjellvik, Kari Furu, Ragnar Nesvåg, Marte Handal, (2016). Antidepressant drug use among adolescents during 2004–2013: a population-based register linkage study. Acta Psychiatrica Scandinavica s. 420-429. doi: 10.1111/acps.12633
- Monica Aas, Ole Andreas Andreassen, Sofie Ragnhild Aminoff, Ann Færden, Kristin Lie Romm, Ragnar Nesvåg, Akiah Ottesen Berg, Carmen Elisabeth Simonsen, Ingrid Agartz, Ingrid Melle, (2016). A history of childhood trauma is associated with slower improvement rates: Findings from a one-year follow-up study of patients with a first-episode psychosis. BMC Psychiatry doi: 10.1186/s12888-016-0827-4
- Anne Høye, Ragnar Nesvåg, Ted Reichborn-Kjennerud, Bjarne K. Jacobsen, (2016). Sex differences in mortality among patients admitted with affective disorders in North Norway: A 33-year prospective register study. Bipolar Disorders s. 272-281. doi: 10.1111/bdi.12389
- Kjetil Nordbø Jørgensen, Stener Nerland, Linn Christin Bonaventure Norbom, Nhat Trung Doan, Ragnar Nesvåg, Lynn Mørch-Johnsen, Unn Kristin H. Haukvik, Ingrid Melle, Ole Andreas Andreassen, Lars Tjelta Westlye, Ingrid Agartz, (2016). Increased MRI-based cortical grey/white-matter contrast in sensory and motor regions in schizophrenia and bipolar disorder. Psychological Medicine s. 1971-1985. doi: 10.1017/S0033291716000593
- Unn Kristin H. Haukvik, Cecilie Bhandari Hartberg, Stener Nerland, Kjetil Nordbø Jørgensen, Elisabeth Lange, Carmen Elisabeth Simonsen, Ragnar Nesvåg, Anders Dale, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2016). No progressive brain changes during a 1-year follow-up of patients with first-episode psychosis. Psychological Medicine s. 589-598. doi: 10.1017/S003329171500210X
- Kjetil Nordbø Jørgensen, Ragnar Nesvåg, Sindre Gunleiksrud, Andrea Raballo, Erik Gunnar Jönsson, Ingrid Agartz, (2015). First- and second-generation antipsychotic drug treatment and subcortical brain morphology in schizophrenia. European Archives of Psychiatry and Clinical Neuroscience doi: 10.1007/s00406-015-0650-9
- Ragnar Nesvåg, Gun Peggy Knudsen, Inger Johanne Bakken, Anne Høye, Eivind Ystrøm, Pål Surén, Anne Reneflot, Camilla Stoltenberg, Ted Reichborn-Kjennerud, (2015). Substance use disorders in schizophrenia, bipolar disorder, and depressive illness: a registry-based study. Social Psychiatry and Psychiatric Epidemiology s. 1267-1276. doi: 10.1007/s00127-015-1025-2
- Elizabeth Ann Barrett, Erlend Mork, Ann Færden, Ragnar Nesvåg, Ingrid Agartz, Ole Andreas Andreassen, Ingrid Melle, (2015). The development of insight and its relationship with suicidality over one year follow-up in patients with first episode psychosis. Schizophrenia Research s. 97-102. doi: 10.1016/j.schres.2015.01.004
- Lynn Mørch-Johnsen, Ragnar Nesvåg, Ann Færden, Unn Kristin H. Haukvik, Kjetil Nordbø Jørgensen, Elisabeth Lange, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2015). Brain structure abnormalities in first-episode psychosis patients with persistent apathy. Schizophrenia Research s. 59-64. doi: 10.1016/j.schres.2015.03.001
- Inger Johanne Bakken, Eline Revdal, Ragnar Nesvåg, Eiliv Brenner, Gun Peggy Knudsen, Pål Suren, Sara Ghaderi, Nina Gunnes, Per Magnus, Ted Reichborn-Kjennerud, Camilla Stoltenberg, Lill Trogstad, Siri Eldevik Håberg, Eylert Brodtkorb, (2014). Substance use disorders and psychotic disorders in epilepsy: a population-based registry study. Epilepsy Research s. 1435-1443. doi: 10.1016/j.eplepsyres.2014.06.021
- Ragnar Nesvåg, M Schaer, Unn Kristin H. Haukvik, Lars Tjelta Westlye, Lars Morten Rimol, Elisabeth Lange, Cecilie Bhandari Hartberg, MC Ottet, Ingrid Melle, Ole Andreas Andreassen, EG Jonsson, Ingrid Agartz, S Eliez, (2014). Reduced brain cortical folding in schizophrenia revealed in two independent samples. Schizophrenia Research s. 333-338. doi: 10.1016/j.schres.2013.11.032
- Elisabeth Lange, Ragnar Nesvåg, Petter Andreas Ringen, Cecilie Bhandari Hartberg, Unn Kristin H. Haukvik, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2014). One year follow-up of alcohol and illicit substance use in first-episode psychosis: Does gender matter?. Comprehensive Psychiatry s. 274-282. doi: 10.1016/j.comppsych.2013.08.018
- Ann Færden, Elizabeth Ann Barrett, Ragnar Nesvåg, Svein Friis, Arnstein Finset, Stephen R. Marder, Joseph Ventura, Ole Andreas Andreassen, Ingrid Agartz, Ingrid Melle, (2013). Apathy, poor verbal memory and male gender predict lower psychosocial functioning one year after the first treatment of psychosis. Psychiatry Research s. 55-61. doi: 10.1016/j.psychres.2013.02.007
- Ragnar Nesvåg, Ørjan Bergmann, Lars Morten Rimol, Elisabeth Lange, Unn Kristin H. Haukvik, Cecilie Bhandari Hartberg, Thomas Fagerberg, Erik Söderman, Erik G. Jönsson, Ingrid Agartz, (2012). A 5-year follow-up study of brain cortical and subcortical abnormalities in a schizophrenia cohort. Schizophrenia Research s. 209-216. doi: 10.1016/j.schres.2012.10.004
- Unn Kristin H. Haukvik, M Schaer, Ragnar Nesvåg, Thomas McNeil, Cecilie Bhandari Hartberg, Erik G. Jönsson, S Eliez, Ingrid Agartz, (2012). Cortical folding in Broca's area relates to obstetric complications in schizophrenia patients and healthy controls. Psychological Medicine s. 1329-1337. doi: 10.1017/S0033291711002315
- Lars Morten Rimol, Ragnar Nesvåg, Donald J. Hagler, Ørjan Bergmann, Christine Fennema-Notestine, Cecilie Bhandari Hartberg, Unn Kristin H. Haukvik, Elisabeth Lange, Chris J. Pung, ANDRES SERVER ALONSO, Ingrid Melle, Ole Andreas Andreassen, Ingrid Agartz, Anders M. Dale, (2012). Cortical Volume, Surface Area, and Thickness in Schizophrenia and Bipolar Disorder. Biological Psychiatry s. 552-560. doi: 10.1016/j.biopsych.2011.11.026
- Cecilie Bhandari Hartberg, Kjetil Søren Sundet, Lars Morten Rimol, Unn Kristin H. Haukvik, Elisabeth Lange, Ragnar Nesvåg, Anders Dale, Ingrid Melle, Ole Andreas Andreassen, Ingrid Agartz, (2011). Brain Cortical Thickness and Surface Area Correlates of Neurocognitive Performance in Patients with Schizophrenia, Bipolar Disorder, and Healthy Adults. Journal of the International Neuropsychological Society s. 1080-1093. doi: 10.1017/S1355617711001081
- Cecilie Bhandari Hartberg, Kjetil Søren Sundet, Lars Morten Rimol, Unn Kristin H. Haukvik, Elisabeth Lange, Ragnar Nesvåg, Ingrid Melle, Ole Andreas Andreassen, Ingrid Agartz, (2011). Subcortical brain volumes relate to neurocognition in schizophrenia and bipolar disorder and healthy controls. Progress in Neuro-psychopharmacology and Biological Psychiatry s. 1122-1130. doi: 10.1016/j.pnpbp.2011.03.014
- Lars Morten Rimol, Cecilie Bhandari Hartberg, Ragnar Nesvåg, C Fennema-Notestine, DJ Hagler, CJ Pung, RG Jennings, Unn Kristin H. Haukvik, Elisabeth Lange, Per Hjalmar Nakstad, Ingrid Melle, Ole Andreas Andreassen, AM Dale, Ingrid Agartz, (2010). Cortical Thickness and Subcortical Volumes in Schizophrenia and Bipolar Disorder. Biological Psychiatry s. 41-50. doi: 10.1016/j.biopsych.2010.03.036
- Unn Kristin H. Haukvik, Thomas F McNeil, Ragnar Nesvåg, Erik Söderman, Erik Jönsson, Ingrid Agartz, (2010). No effect of obstetric complications on basal ganglia volumes in schizophrenia. Progress in Neuro-psychopharmacology and Biological Psychiatry s. 619-623. doi: 10.1016/j.pnpbp.2010.02.024
- Ragnar Nesvåg, Elisabeth Lange, Ann Færden, Elisabeth Ann Barrett, Bjørn Emilsson, Petter Andreas Ringen, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2010). The use of screening instruments for detecting alcohol and other drug use disorders in first-episode psychosis. Psychiatry Research s. 228-234. doi: 10.1016/j.psychres.2010.01.007
- Ann Færden, Arnstein Finset, Svein Friis, Ingrid Agartz, Elisabeth Ann Barrett, Ragnar Nesvåg, Ole Andreas Andreassen, Stephen R. Marder, Ingrid Melle, (2010). Apathy in first episode psychosis patients: One year follow up. Schizophrenia Research s. 20-26. doi: 10.1016/j.schres.2009.10.014
- Elizabeth Ann Barrett, Kjetil Søren Sundet, Ann Færden, Ragnar Nesvåg, Ingrid Agartz, Roar Fosse, Erlend Mork, Nils Eiel Steen, Ole Andreas Andreassen, Ingrid Melle, (2010). Suicidality before and in the early phases of first episode psychosis. Schizophrenia Research s. 11-17. doi: 10.1016/j.schres.2010.03.022
- Ragnar Nesvåg, P Saetre, Glenn Lawyer, Erik G. Jönsson, Ingrid Agartz, (2009). The relationship between symptom severity and regional cortical and grey matter volumes in schizophrenia. Progress in Neuro-psychopharmacology and Biological Psychiatry s. 482-490. doi: 10.1016/j.pnpbp.2009.01.013
- David Glenn Lawyer, Ragnar Nesvåg, Katarina Varnäs, G Okugawa, Ingrid Agartz, (2009). Grey and White Matter Proportional Relationships in the Cerebellar Vermis Altered in Schizophrenia. Cerebellum s. 52-60. doi: 10.1007/s12311-008-0071-7
- Ann Færden, Svein Friis, Ingrid Agartz, Elisabeth Ann Barrett, Ragnar Nesvåg, Arnstein Finset, Ingrid Melle, (2009). Apathy and Functioning in First-Episode Psychosis. Psychiatric Services s. 1495-1503.
- David Glenn Lawyer, Egil Ferkingstad, Ragnar Nesvåg, I Agartz, (2009). Local and covariate-modulated false discovery rates applied in neuroimaging. NeuroImage s. 213-219. doi: 10.1016/j.neuroimage.2009.03.047
- Ann Færden, Ragnar Nesvåg, Steve Marder, (2008). Definitions of the term recovered in schizophrenia and other disorders. Psychopathology s. 271-278.
- Petter Andreas Ringen, Trine Vik Lagerberg, Astrid Brate Birkenæs, JA Engh, Ann Færden, Halldóra Jónsdóttir, Ragnar Nesvåg, Svein Friis, S Opjordsmoen, Frode Larsen, Ingrid Melle, Ole Andreas Andreassen, (2008). Differences in prevalence and patterns of substance use in schizophrenia and bipolar disorder. Psychological Medicine s. 1241-1249. doi: 10.1017/S003329170700236X
- Ann Færden, Ragnar Nesvåg, AE Barett, Ingrid Agartz, Arnstein Finset, Svein Friis, Jan Ivar Rossberg, Ingrid Melle, (2008). Assessing apathy: The use of the Apathy Evaluation Scale in first episode psychosis. European psychiatry s. 33-39. doi: 10.1016/j.eurpsy.2007.09.002
- Petter Andreas Ringen, Ingrid Melle, Astrid Brate Birkenæs, John Engh, Ann Færden, Halldóra Jónsdóttir, Ragnar Nesvåg, Anja Vaskinn, Svein Friis, Frode Larsen, Opjordsmoen Stein E. Ilner, Kjetil Søren Sundet, Ole Andreas Andreassen, (2008). Illicit drug use in patients with psychotic disorders compared with that in the general population: a cross-sectional study. Acta Psychiatrica Scandinavica s. 133-138. doi: 10.1111/j.1600-0447.2007.01135.x
- Katarina Varnäs, Anders Martin Fjell, Kristine B Walhovd, Arnoldo Frigessi, EG Jonsson, Ingrid Agartz, Ragnar Nesvåg, Glenn Lawyer, (2008). Regional thinning of the cerebral cortex in schizophrenia: Effects of diagnosis, age and antipsychotic medication. Schizophrenia Research doi: 10.1016/j.schres.2007.09.015
- Anne Høye, Bjarne K. Jacobsen, Jørgen Gustav Bramness, Ragnar Nesvåg, Ted Reichborn-Kjennerud, Ina Heidi Heiberg, (2021). Correction to: Total and cause-specific mortality in patients with personality disorders: the association between comorbid severe mental illness and substance use disorders. Social Psychiatry and Psychiatric Epidemiology doi: 10.1007/s00127-021-02124-7
- Svetlana Skurtveit, Jørgen Gustav Bramness, Vidar Hjellvik, Ingeborg Hartz, Ragnar Nesvåg, Lars Johan Hauge, Marte Handal, (2018). Increase in diagnosis of depressive disorders contributes to the increase in antidepressant use in adolescents. Pharmacoepidemiology and Drug Safety
- Ingeborg Hartz, Svetlana Skurtveit, Vidar Hjellvik, Kari Furu, Ragnar Nesvåg, Marte Handal, (2016). Antidepressant Drug use Among Adolescents in Norway from 2004 to 2013‐ A Population‐Based Register Study. Pharmacoepidemiology and Drug Safety
- Ragnar Nesvåg, Ingeborg Hartz, Jørgen Gustav Bramness, Vidar Hjellvik, Marte Handal, Svetlana Skurtveit, (2016). Differences Between Genders in Antipsychotic Medication Among Children and Adolescents – Patterns in Use and Underlying Mental Disorders. Pharmacoepidemiology and Drug Safety
- Ragnar Nesvåg, Eivind Ystrøm, Gunnar Kvåle, (2016). Cannabis forverrer psykisk helse. Aftenposten (morgenutg. : trykt utg.)
- Eivind Ystrøm, Ted Reichborn-Kjennerud, Fartein Ask Torvik, Ragnar Nesvåg, (2015). Common genetic and environmental risk factors for psychosis, mania, and personality disorders.
- Ragnar Nesvåg, Jørgen Gustav Bramness, Eivind Ystrøm, (2015). The link between use of psychedelic drugs and mental health problems. Journal of Psychopharmacology s. 1035-1040. doi: 10.1177/0269881115596156
- Nikolai Olavi Czajkowski, Steven H. Aggen, Gun Peggy Knudsen, Robert F Krueger, Michael C. Neale, Eivind Ystrøm, Ragnar Nesvåg, Kenneth S. Kendler, Ted Reichborn-Kjennerud, (2015). Modest overlap in the genetic influences underlying normal and abnormal personality.
- Eivind Ystrøm, Ted Reichborn-Kjennerud, Nathan Gillespie, Fartein Ask Torvik, Nikolai Olavi Czajkowski, Robert F Krueger, Kenneth S. Kendler, Ragnar Nesvåg, (2015). Psychosis, mania and personality disorders.
- Ingeborg Hartz, Svetlana Skurtveit, Vidar Hjellvik, Kari Furu, Ragnar Nesvåg, Marte Handal, (2015). Antidepressant drug use among adolescents during 2004-2013 – a population-based linkage study between the Nationwide prescription database and patient register . Norsk Epidemiologi, Supplement s. 95-95.
- Kjetil Nordbø Jørgensen, Stener Nerland, Linn Christin Bonaventure Norbom, Nhat Trung Doan, Ragnar Nesvåg, Unn Kristin H. Haukvik, Ingrid Melle, Ole Andreas Andreassen, Lars Tjelta Westlye, Ingrid Agartz, (2015). Increased cortical gray/white matter intensity contrast in schizophrenia and bipolar disorder compared to healthy controls.
- Lynn Mørch-Johnsen, Ragnar Nesvåg, Ann Færden, Unn Kristin H. Haukvik, Kjetil Nordbø Jørgensen, Elisabeth Lange, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2014). Brain structure changes in first-episode psychosis patients with persistent apathy. Schizophrenia Research s. S210-S210. doi: 10.1016/S0920-9964(14)70608-5
- Lynn Mørch-Johnsen, Ragnar Nesvåg, Ann Færden, Unn Kristin H. Haukvik, Kjetil Nordbø Jørgensen, Elisabeth Lange, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2014). Brain structure changes in first-episode psychosis patients with persistent apathy.
- Unn Kristin H. Haukvik, M Schaer, Ragnar Nesvåg, Thomas McNeil, Cecilie Bhandari Hartberg, Erik G. Jönsson, Stephan Eliez, Ingrid Agartz, (2010). CORTICAL FOLDING PATTERNS AND OBSTETRIC COMPLICATIONS IN SCHIZOPHRENIA. Schizophrenia Research s. 226-227. doi: 10.1016/j.schres.2010.02.331
- Lars Morten Rimol, Cecilie Bhandari Hartberg, Ragnar Nesvåg, Christine Fennema-Notestine, D. Hagler, CJ Pung, RG Jennings, Unn Kristin H. Haukvik, Elisabeth Lange, Per Hjalmar Nakstad, Ingrid Melle, Ole Andreas Andreassen, Anders M. Dale, Ingrid Agartz, (2010). CORTICAL THICKNESS AND SUBCORTICAL VOLUMES IN SCHIZOPHRENIA AND BIPOLAR DISORDER. Schizophrenia Research s. 459-459. doi: 10.1016/j.schres.2010.02.857
- Ragnar Nesvåg, M Schaer, Unn Kristin H. Haukvik, Lars Morten Rimol, Elisabeth Lange, Cecilie Bhandari Hartberg, EG Jonsson, I Melle, OA Andreassen, Ingrid Agartz, S Eliez, (2010). REDUCED BRAIN CORTICAL FOLDING IN SCHIZOPHRENIA. Schizophrenia Research s. 342-342.
- EH Lange, Ragnar Nesvåg, B Emilsson, Ole Andreas Andreassen, Ingrid Melle, Ingrid Agartz, (2009). ALCOHOL AND ILLICIT DRUG USE AFTER ONE YEAR COMPARED WITH BASELINE IN NORWEGIAN FIRST-EPISODE PSYCHOSIS PATIENTS. Schizophrenia Bulletin s. 308-308.
- A Faerden, Anja Vaskinn, Arnstein Finset, Ingrid Agartz, Elisabeth Ann Barrett, Svein Friis, Carmen Elisabeth Simonsen, Ragnar Nesvåg, Ole Andreas Andreassen, Ingrid Melle, (2009). THE NEGATIVE SUBSYMPTOM APATHY AND ITS RELATION TO EXECUTIVE FUNCTIONING IN FIRST EPISODE PSYCHOSIS. Schizophrenia Bulletin s. 274-274.
- KM Henriksson, BD Kelly, A Lane, Ingrid Agartz, Ragnar Nesvåg, E Cantor-Graae, E O'Callaghan, TF McNeil, (2008). Age does not explain high rates of minor physical anomalies in schizophrenia patients. Psychological Medicine doi: 10.1017/S0033291707000992
- BD Kelly, A Lane, G Lawyer, Ingrid Agartz, TF McNeil, KM Henriksson, Ragnar Nesvåg, (2008). Craniofacial dysmorphology and cortical thickness in men with schizophrenia. Schizophrenia Research s. 322-323. doi: 10.1016/j.schres.2008.04.014
- Petter Andreas Ringen, Trine Vik Lagerberg, Astrid Brate Birkenæs, John Engh, Ann Færden, Halldóra Jónsdóttir, Ragnar Nesvåg, Svein Friis, Stein Opjordsmoen, Frode Larsen, Ingrid Melle, Ole Andreas Andreassen, (2008). Differences in prevalence and patterns of substance use in schizophrenia and bipolar disorder.