Marit Knapstad
Research professor
Contact
Mob: +47 992 35 930
Send email {model.translations.sendEmailTo} Marit.Knapstad@fhi.no
Department
Responsibilities
Mental health and psychological interventions (Prompt Mental Health Care (IAPT Norway), prevention and early intervention, CBT for depression and anxiety). Public mental health (Mental healthcare access, health-related behaviors (County Public Mental Health Survey), mental health trends, wellbeing). Work and health. Health promotion and prevention. Psychiatric epidemiology.
Projects and publications
- Leif Edvard Aarø, Marit Knapstad, Otto Robert Frans Smith, (2025). Positive mental wellbeing or symptoms of depression? Discriminant validity of the Warwick-Edinburgh Mental Wellbeing Scale. BMC Psychiatry s. 1-14. doi: 10.1186/s12888-025-06922-0
- Otto Robert Frans Smith, David M. Clark, Gunnel Hensing, Richard Layard, Marit Knapstad, (2025). Cost-benefit of IAPT Norway and effects on work-related outcomes and health care utilization: Results from a randomized controlled trial using registry-based data. Psychological Medicine s. 1-12. doi: 10.1017/S003329172500025X
- Tonje Catrin Hakvaag, Marit Knapstad, Tore Tjora, (2025). Office Level Variation in Benefit Duration for Service Users Receiving Work Assessment Allowance: A Norwegian Longitudinal Multilevel Register Study. Scandinavian Journal of Public Administration (SPJA) s. 59-75. doi: 10.58235/sjpa.2024.22888
- Leif Edvard Aarø, Otto Robert Smith, Mogens Trab Damsgaard, Anne-Siri Fismen, Marit Knapstad, Nelli Lyyra, Oddrun Samdal, Einar Baldvin Thorsteinsson, Charli Eriksson, (2025). Four scales measuring mental wellbeing in the Nordic countries: do they tell the same story?. Health and Quality of Life Outcomes s. 1-23. doi: 10.1186/s12955-025-02351-5
- Marit Knapstad, Lauren Lissner, Cecilia Björkelund, Kristina Holmgren, (2025). Mental stress due to poor organizational climate and high work commitment as predictor of 10-year registered sickness absence: a cohort study based on The Population Study of Women in Gothenburg. Scandinavian Journal of Primary Health Care s. 1-12. doi: 10.1080/02813432.2025.2466177
- Otto R. F. Smith, Marit Knapstad, Leif Edvard Aarø, (2025). Minimizing patient burden in outcome monitoring: The case for abbreviated versions of PHQ-9, GAD-7 and WSAS. Journal of Affective Disorders s. 237-244. doi: 10.1016/j.jad.2024.12.089
- Børge Sivertsen, Jens Christoffer Skogen, Anne Reneflot, Marit Knapstad, Otto Robert Frans Smith, Leif Edvard Aarø, Benedicte Kirkøen, Bengt Oscar Lagerstrøm, Ann Kristin Skrindo Knudsen, (2024). Assessing Diagnostic Precision: Adaptations of the Hopkins Symptom Checklist (HSCL-5/10/25) Among Tertiary-Level Students in Norway. Clinical Psychology in Europe doi: 10.32872/cpe.13275
- Leif Edvard Aarø, Marit Knapstad, Thomas Sevenius Nilsen, Jens Christoffer Skogen, Ragnhild Bang Nes, Tony Mathias Leino, Ingunn Agnete Riise, Rune Johansen, Liv Grøtvedt, Øystein Vedaa, Ole Trygve Stigen, Anne Reneflot, Hanne Løvdal Gulseth, Knut Inge Klepp, (2024). The Norwegian Counties Public Health Survey (NCPHS): a design study. Scandinavian Journal of Public Health doi: 10.1177/14034948241287853
- Leif Edvard Aarø, Eyvind Ohm, Jens Christoffer Skogen, Thomas Sevenius Nilsen, Marit Knapstad, Øystein Vedaa, Ragnhild Bang Nes, Benjamin Matthew Clarsen, Knut Inge Klepp, (2023). A cross-sectional study of the relationship between injuries and quality of life, psychological distress, sleeping problems, and global subjective health in adults from three Norwegian counties. Health and Quality of Life Outcomes s. 1-10. doi: 10.1186/s12955-023-02191-1
- Otto Robert Frans Smith, Leif Edvard Aarø, Marit Knapstad, (2023). The Importance of Symptom Reduction for Functional Improvement after Cognitive Behavioral Therapy for Anxiety and Depression: A Causal Mediation Analysis. Psychotherapy and Psychosomatics s. 193-202. doi: 10.1159/000530650
- Elin Hanevik, Frida M. G. Røvik, Tormod Bøe, Marit Knapstad, Otto R. F. Smith, (2023). Client predictors of therapy dropout in a primary care setting: a prospective cohort study. BMC Psychiatry doi: 10.1186/s12888-023-04878-7
- Leif Edvard Aarø, Tony Mathias Leino, Øystein Vedaa, Marit Knapstad, Jens Christoffer Skogen, Thomas Sevenius Nilsen, Mats Svalebjørg, Knut Inge Klepp, (2023). Behavioural precautions to avoid transmission of the COVID-19 virus – low educated groups are not always lagging behind. Journal of Health Inequalities s. 16-28. doi: 10.5114/jhi.2022.123437
- Solbjørg Makalani Myrtveit Sæther, Marit Knapstad, Nick Grey, Otto Robert Frans Smith, (2022). Moderators of treatment effect of Prompt Mental Health Care compared to treatment as usual: Results from a randomized controlled trial. Behaviour Research and Therapy s. 1-12. doi: 10.1016/j.brat.2022.104198
- Otto Robert Frans Smith, Solbjørg Makalani Myrtveit Sæther, Ellen Merethe Melingen Haug, Marit Knapstad, (2022). Long-term outcomes at 24- and 36-month follow-up in the intervention arm of the randomized controlled trial of Prompt Mental Health Care. BMC Psychiatry doi: 10.1186/s12888-022-04227-0
- Børge Sivertsen, Marit Knapstad, Keith Petrie, Rory O'Connor, Kari Jussi Lønning, Mari Hysing, (2022). Changes in mental health problems and suicidal behaviour in students and their associations with COVID-19-related restrictions in Norway: A national repeated cross-sectional analysis. BMJ Open doi: 10.1136/bmjopen-2021-057492
- Tonje Catrin Hakvaag, Marit Knapstad, Jone Ravndal Bjørnestad, Tore Tjora, (2022). A scooping review of Scandinavian studies of sick-listed' and social insurance officers' experiences of their encounters'. Social Policy & Administration s. 595-616. doi: 10.1111/spol.12796
- Thomas Hansen, Thomas Sevenius Nilsen, Marit Knapstad, Vegard Fykse Skirbekk, Jens Christoffer Skogen, Øystein Vedaa, Ragnhild Bang Nes, (2021). Covid-fatigued? A longitudinal study of Norwegian older adults’ psychosocial well-being before and during early and later stages of the COVID-19 pandemic. European Journal of Ageing s. 1-11. doi: 10.1007/s10433-021-00648-0
- Linn Vathne Lervik, Asle Hoffart, Marit Knapstad, Otto Robert Frans Smith, (2021). Exploring the temporal associations between avoidance behavior and cognitions during the course of cognitive behavioral therapy for clients with symptoms of social anxiety disorder. Psychotherapy Research s. 1-15. doi: 10.1080/10503307.2021.1930243
- Linn Vathne Lervik, Marit Knapstad, Asle Hoffart, Otto Robert Frans Smith, (2021). Psychometric Properties of the Norwegian Version of the Cognitive Therapy Adherence and Competence Scale (CTACS) and Its Associations With Outcomes Following Treatment in IAPT Norway. Frontiers in Psychology doi: 10.3389/fpsyg.2021.639225
- Thomas Hansen, Thomas Sevenius Nilsen, Baeksan Yu, Marit Knapstad, Jens Christoffer Skogen, Øystein Vedaa, Ragnhild Bang Nes, (2021). Locked and lonely? A longitudinal assessment of loneliness before and during the COVID-19 pandemic in Norway. Scandinavian Journal of Public Health s. 766-773. doi: 10.1177/1403494821993711
- Marit Knapstad, Robert Frans Otto Smith, (2021). Social anxiety and agoraphobia symptoms effectively treated by Prompt Mental Health Care versus TAU at 6‐ and 12‐month follow‐up: Secondary analysis from a randomized controlled trial. Depression and Anxiety s. 351-360. doi: 10.1002/da.23132
- Solbjørg Makalani Myrtveit Sæther, Marit Knapstad, Nick Grey, Marit Aase Rognerud, Otto Robert Frans Smith, (2020). Long-term outcomes of Prompt Mental Health Care: A randomized controlled trial. Behaviour Research and Therapy s. 1-11. doi: 10.1016/j.brat.2020.103758
- Linn Lervik, Marit Knapstad, Robert Frans Otto Smith, (2020). Process evaluation of Prompt Mental Health Care (PMHC): the Norwegian version of Improving Access to Psychological Therapies. BMC Health Services Research doi: 10.1186/s12913-020-05311-5
- Marit Knapstad, Solbjørg Makalani Myrtveit Sæther, Gunnel Hensing, Otto Robert Frans Smith, (2020). Prompt Mental Health Care (PMHC): work participation and functional status at 12 months post-treatment. BMC Health Services Research doi: 10.1186/s12913-020-4932-1
- Marit Knapstad, Linn Vathne Lervik, Solbjørg Makalani Myrtveit Sæther, Leif Edvard Aarø, Otto Robert Frans Smith, (2019). Effectiveness of prompt mental health care, the Norwegian version of improving access to psychological therapies: A randomized controlled trial. Psychotherapy and Psychosomatics s. 90-105. doi: 10.1159/000504453
- Marit Knapstad, Børge Sivertsen, Ann Kristin Knudsen, Otto Robert Frans Smith, Leif Edvard Aarø, Kari Jussi Lønning, Jens Christoffer Skogen, (2019). Trends in self-reported psychological distress among college and university students from 2010 to 2018. Psychological Medicine doi: 10.1017/S0033291719003350
- Solbjørg Makalani Myrtveit Sæther, Marit Knapstad, Nick Grey, Otto Robert Frans Smith, (2019). Twelve months post-treatment results from the Norwegian version of improving access to psychological therapies. Frontiers in Psychology s. 1-11. doi: 10.3389/fpsyg.2019.02303
- Jens Christoffer Skogen, Marit Knapstad, Otto Robert Frans Smith, Grethe S. Tell, Rolv T. Lie, Thomas Sevenius Nilsen, Leif Edvard Aarø, (2019). Hvordan bør rekrutteringen til folkehelseundersøkelsene gjennomføres?. Tidsskrift for Den norske legeforening (Tidsskriftet) s. 1462-1467. doi: 10.4045/tidsskr.19.0054
- Solbjørg Makalani Myrtveit Sæther, Marit Knapstad, Kristin Gärtner Askeland, Jens Christoffer Skogen, (2019). Alcohol consumption, life satisfaction and mental health among Norwegian college and university students. Addictive Behaviors Reports s. 1-9. doi: 10.1016/j.abrep.2019.100216
- Solbjørg Makalani Myrtveit, Kristin Gärtner Askeland, Ann Kristin Knudsen, Marit Knapstad, Jens Christoffer Skogen, (2019). Risky drinking among Norwegian students: Associations with participation in the introductory week, academic performance and alcohol-related attitudes. Nordic Studies on Alcohol and Drugs (NAD) s. 1-20. doi: 10.1515/nsad-2016-0025
- Eirunn Thun, Børge Sivertsen, Marit Knapstad, Otto Robert Frans Smith, (2019). Unravelling the prospective associations between mixed anxiety-depression and insomnia during the course of cognitive behavioral therapy. Psychosomatic Medicine s. 333-340. doi: 10.1097/PSY.0000000000000676
- Børge Sivertsen, Morten Birkeland Nielsen, Ida E.H. Madsen, Marit Knapstad, Kari Jussi Lønning, Mari Hysing, (2019). Sexual harassment and assault among university students in Norway. A cross-sectional prevalence study. BMJ Open s. 1-10. doi: 10.1136/bmjopen-2018-026993
- Børge Sivertsen, Mari Hysing, Marit Knapstad, Allison G. Harvey, Anne Reneflot, Kari Jussi Lønning, Rory O'Connor, (2019). Suicide attempts and non-suicidal self-harm among university students: Prevalence study. BJPsych Open doi: 10.1192/bjo.2019.4
- Marit Knapstad, Tine Nordgreen, Otto Robert Frans Smith, (2018). Prompt mental health care, the Norwegian version of IAPT: clinical outcomes and predictors of change in a multicenter cohort study. BMC Psychiatry doi: 10.1186/s12888-018-1838-0
- Otto Robert Frans Smith, Daniele Evelin Alves, Marit Knapstad, Ellen Haug, Leif Edvard Aarø, (2017). Measuring mental well-being in Norway: validation of the Warwick-Edinburgh Mental Well-being Scale (WEMWBS). BMC Psychiatry doi: 10.1186/s12888-017-1343-x
- Amie C. Hayley, Luke A. Downey, Con Stough, Børge Sivertsen, Marit Knapstad, Simon Nygaard Øverland, (2016). Social and emotional loneliness and self-reported difficulty initiating andmaintaining sleep (DIMS) in a sample of Norwegian university students. Scandinavian Journal of Psychology s. 91-99. doi: 10.1111/sjop.12343
- Solbjørg Makalani Myrtveit, Kristin Gärtner Askeland, Marit Knapstad, Ann Kristin Knudsen, Jens Christoffer Skogen, (2016). The Norwegian student introductory week: who takes part, and is participation associated with better social integration and satisfaction among students?. European Journal of Higher Education doi: 10.1080/21568235.2016.1252933
- Marit Knapstad, Jesper Löve, Kristina Holmgren, Gunnel Hensing, Simon Nygaard Øverland, (2016). Registry-based analysis of participator representativeness: a source of concern for sickness absence research?. BMJ Open doi: 10.1136/bmjopen-2016-012372
- Solbjørg Makalani Myrtveit, Kristin Gärtner Askeland, Ann Kristin Knudsen, Marit Knapstad, Rune Olsen, Truls Nedregård, Jens Christoffer Skogen, (2016). Risky drinking among Norwegian students: associations with participation in the introductory week, academic performance and alcohol-related attitudes. Nordic Studies on Alcohol and Drugs (NAD) s. 361-380. doi: 10.1515/nsad-2016-0031
- Jens Christoffer Skogen, Robert Stewart, Marit Knapstad, Simon Nygaard Øverland, Arnstein Mykletun, (2014). Early life factors in relation to cardiovacular disease in old age in Bergen: a Norwegian retrospective cohort study based on the Hordaland Study (HUSK). Journal of the Royal Society of Medicine doi: 10.1177/2054270414527935
- Marit Knapstad, Kristina Holmgren, Gunnel Hensing, Simon Nygaard Øverland, (2014). Previous sickness absence and current low perceived social support at work among employees in the general population: A historical cohort study. BMJ Open doi: 10.1136/bmjopen-2014-005963
- Marit Knapstad, Simon Nygaard Øverland, Max Henderson, Kristina Holmgren, Gunnel Hensing, (2014). Shame among long-term sickness absentees: correlates and impact on subsequent sickness absence. Scandinavian Journal of Public Health s. 96-103. doi: 10.1177/1403494813500590
- Jens Christoffer Skogen, Robert Stewart, Arnstein Mykletun, Marit Knapstad, Simon Øverland, (2013). An investigation of factors identified at birth in relation to anxiety and depression in old age: The Hordaland Health Study (HUSK). BMC Psychiatry doi: 10.1186/1471-244X-13-136
- Simon Nygaard Øverland, Marit Knapstad, Ingvard Wilhelmsen, Arnstein Mykletun, Nick Glozier, (2011). Do gastrointestinal complaints increase the risk for subsequent medically certified long-term sickness absence? The HUSK study. BMC Gastroenterology doi: 10.1186/1471-230X-11-88
- Rolf Reber, Pascal Wurtz, Marit Knapstad, Linn Vathne Lervik, (2010). Polarity correspondence in comparative number magnitude judgments. Psychonomic Bulletin & Review s. 219-223. doi: 10.3758/PBR.17.2.219
- Marit Knapstad, Gunnhild Johnsen Hjetland, Turi Reiten Finserås, Robert Smith, (2025). Evaluering av veiledet internettbehandling ved Rask psykisk helsehjelp: En randomisert kontrollert studie .
- Marit Knapstad, Ingebjørg Louise Rockwell Djupedal, Ragnhild Bang Nes, Thomas Sevenius Nilsen, Leif Edvard Aarø, Øystein Vedaa, (2025). Livskvalitet, subjektiv helse, sosiale relasjoner og funksjonsnivå blant eldre i Bergen 2024: En digital og postal spørreskjemaundersøkelse .
- Øystein Vedaa, Marit Knapstad, Thomas Sevenius Nilsen, Leif Edvard Aarø, Ragnhild Bang Nes, Lema Hussaini, Truc Trung Nguyen, Thor Indseth, (2025). Folkehelseundersøkelsen i Oslo 2024: Fremgangsmåte og utvalgte resultater.
- Marit Knapstad, Ragnhild Bang Nes, Thomas Sevenius Nilsen, Jens Christoffer Skogen, Victor Daniel Lode, Ingunn Agnete Riise, Leif Edvard Aarø, (2024). Folkehelseundersøkelsen i Rogaland 2023: Fremgangsmåte og utvalgte resultater.
- Marit Knapstad, Thomas Sevenius Nilsen, Jens Christoffer Skogen, Ragnhild Bang Nes, Victor Daniel Lode, Ingunn Agnete Riise, Leif Edvard Aarø, (2024). Folkehelseundersøkelsen i Agder 2023: fremgangsmåte og utvalgte resultater.
- Tony Mathias Leino, Thomas Sevenius Nilsen, Leif Edvard Aarø, Jens Christoffer Skogen, Ragnhild Bang Nes, Victor Daniel Lode, Marit Knapstad, (2023). Folkehelseundersøkelsen i Innlandet 2023: Fremgangsmåte og utvalgte resultater.
- Marit Knapstad, Tony Mathias Leino, (2023). Folkehelseundersøkinga i Vestland 2022: Utvalde resultat basert på tilleggsspørsmåla i undersøkinga .
- Tony Mathias Leino, Thomas Sevenius Nilsen, Marit Knapstad, (2023). Koronaundersøkinga i Vestland 2021: Framgangsmåte og utvalde resultat.
- Tony Mathias Leino, Leif Edvard Aarø, Marit Knapstad, Jens Christoffer Skogen, Øystein Vedaa, (2022). Opplevd tiltaksbyrde under koronapandemien: Resultater fra fire fylker desember 2021..
- Marit Knapstad, Jens Christoffer Skogen, Gunnhild Johnsen Hjetland, Thomas Sevenius Nilsen, Tony Mathias Leino, Ragnhild Bang Nes, Leif Edvard Aarø, (2022). Folkehelseundersøkinga i Vestland 2022: Framgangsmåte og utvalde resultat .
- Marit Knapstad, Jens Christoffer Skogen, Tony Mathias Leino, Thomas Sevenius Nilsen, Ragnhild Bang Nes, Leif Edvard Aarø, (2022). Folkehelseundersøkelsen i Viken 2021: Fremgangsmåte og utvalgte resultater.
- Marit Knapstad, Jens Christoffer Skogen, Tony Mathias Leino, Thomas Sevenius Nilsen, Ragnhild Bang Nes, Leif Edvard Aarø, (2022). Folkehelseundersøkelsen – Helse og trivsel i Vestfold og Telemark 2021: Fremgangsmåte og utvalgte resultater.
- Leif Edvard Aarø, Øystein Vedaa, Tone Bruun, Thomas Sevenius Nilsen, Rune Johansen, Marit Knapstad, Jens Christoffer Skogen, Knut Inge Klepp, (2021). Koronaatferd og landbakgrunn i fire fylker. Etterlevelse og holdninger til offisiellesmittevernråd, opplevd engstelse, psykiske plager og endringer i sosiale kontakter etter landbakgrunn. Resultater fra undersøkelser i fire fylker under koronapandemien.
- Marit Knapstad, Thomas Sevenius Nilsen, Leif Edvard Aarø, Adrian Schønning, Ragnhild Bang Nes, Jens Christoffer Skogen, (2021). Folkehelseundersøkinga i Møre og Romsdal 2021: Framgangsmåte og utvalde resultat.
- Marianne A Riise Bergsaker, Bernt Bratsberg, Anita Odveig Daae, Signe Agnes Flottorp, Frode Forland, Ellen Furuseth, Anna Aasen Godøy, Rannveig Kaldager Hart, Njål Høstmælingen, Thor Indseth, Marit Knapstad, Ann Kristin Skrindo Knudsen, Angela Susan Labberton, Ragnhild Bang Nes, Thomas Nilsen, Heid Nøkleby, Trygve Ottersen, Bjørn-Atle Reme, Christina Lill Rolfheim-Bye, John-Arne Røttingen, Oddbjørn Raaum, Jens Christoffer Skogen, Pål Suren, Kjetil Elias Telle, Øystein Vedaa, Jonathan Wörn, Leif Edvard Aarø, Hilde Marie Tvedten, Eirik Frønæs Vikum, Merete Kile Holtermann, Vilde Bergstad Larsen, (2021). Folkehelserapportens temautgave 2021. Folkehelsen etter covid-19. Pandemiens konsekvenser for ulike grupper i befolkningen.
- Jens Christoffer Skogen, Thomas Sevenius Nilsen, Gunnhild Johnsen Hjetland, Marit Knapstad, Ragnhild Bang Nes, Leif Edvard Aarø, Øystein Vedaa, (2020). Folkehelseundersøkelsen i Rogaland 2020: Fremgangsmåte og utvalgte resultater.
- Marit Knapstad, Jens Christoffer Skogen, Thomas Sevenius Nilsen, Leif Edvard Aarø, (2019). Folkehelseundersøkinga i Sogn og Fjordane: Framgangsmåte og utvalde resultat .
- Marit Knapstad, Ove Heradstveit, Børge Sivertsen, (2018). Studentenes Helse- og Trivselsundersøkelse 2018 (SHoT)/ HELT ÆRLIG-undersøkelsen .
- Robin Ulriksen, Marit Knapstad, (2016). Digital mobbing. Kunnskapsoppsummering over forskning på effekter av tiltak..
- Otto Robert Frans Smith, Daniele Evelin Alves, Marit Knapstad, (2016). Rask psykisk helsehjelp: Evaluering av de første 12 pilotene i Norge.
- Therese Kristine Dalsbø, Marit Knapstad, (2015). Arbeidsplasstiltak får trolig flere sykemeldte tilbake på jobb (Cochrane - kort oppsummert).
- Marit Knapstad, Simon Nygaard Øverland, (2015). Psychological factors in long-term sickness absence: the role of shame and social support. Epidemiological studies based on the Health Assets Project.
- Therese Kristine Dalsbø, Marit Knapstad, (2014). Arbeidsmiljøfaktorer kan påvirke ansattes psykiske helse (omtale av SBU-rapport).
- Therese Kristine Dalsbø, Kristin Thuve Dahm, Astrid Austvoll-Dahlgren, Marit Knapstad, Malene Wøhlk Gundersen, Liv Merete Reinar, (2013). Arbeidslivsbaserte tiltak for psykisk helse hos ansatte.
- Leif Edvard Aarø, Thomas Sevenius Nilsen, Marit Knapstad, Jens Christoffer Skogen, Ragnhild Bang Nes, Øystein Vedaa, Knut Inge Klepp, (2024). The Norwegian Counties Public Health Survey (NCPHS). European Journal of Public Health s. iii821-iii821. doi: 10.1093/eurpub/ckae144.2118
- Sebastian Brun Bjørkheim, Bjørn Sætrevik, Marit Knapstad, (2022). Hvilke grunner har folk til å ikke følge smitteverntiltakene?. Forskersonen.no
- Tonje Catrin Hakvaag, Marit Knapstad, Jone Ravndal Bjørnestad, Tore Tjora, (2021). Interpersonal encounters in Return to Work.
- Tonje Catrin Hakvaag, Marit Knapstad, Jone Ravndal Bjørnestad, Tore Tjora, (2021). Factors perceived to impact return to work in Scandinavian sickness insurance: a scoping review of encounters between sick-listed and social insurance officers.
- Otto Robert Frans Smith, Marit Knapstad, Daniele Evelin Alves, Leif Edvard Aarø, (2017). Initial results of prompt mental health care, the Norwegian version of improving access to psychological therapies. Psychotherapy and Psychosomatics s. 382-384. doi: 10.1159/000477668
- Otto Robert Frans Smith, Daniele Evelin Alves, Marit Knapstad, (2016). Status fra evalueringsarbeidet.
- Therese Kristine Dalsbø, Marit Knapstad, (2015). Stress hos helsepersonell kan forebygges (Cochrane - kort oppsummert). Cochrane Database of Systematic Reviews
- Rolf Reber, Pascal Wurtz, Marit Knapstad, Linn Vathne Lervik, (2009). A Polarity Correspondence Account of Comparative Number Magnitude Judgments.