Appendix

Youth in Iceland (Cross-sectional) and LIFECOURSE (Longitudinal)
Country	Iceland
Target group	Children and adolescents (separate surveys for three age groups: 10–12; 13–15; 16–18-year-olds)
First data collection	1992 (14–15 years), 2001 (10–12), 2004 (16–18). NB: Initially started as a survey instrument to monitor substance use, many early surveys focus on this.
Data collection frequency	Broadly every other year. Grades 5–7 odd years, older groups on even years. LIFECOURSE longitudinal subset of adolescents born in 2004, surveyed annually in 2017–2020.
Contact information	thorhildurh@ru.is
LGBTI+ -related questions in the survey
Sexuality	Ages 10–12 – no questions Ages 13–15 (2016, 2018); two questions Where would you place yourself on a scale measuring sexual attraction to the opposite sex? Where would you place yourself on a scale measuring sexual attraction to the same sex? Response options: 1–5 1=Not at all attracted, 5=Very attracted Ages 16–18 (2004, 2013, 2016, 2018) Same or similar questions as above for ages 13–15. Additional questions sexual activity and relationships with opposite/same sex in 2004 and 2013.
Gender	For most years the question was a binary option: Q: “Are you a boy or a girl” A: Boy or girl (two options) Three level response introduced 2018 and later: Q: What is your gender? A: Boy, girl, Other/Non-binary (three options) Ages 10–12: 2021 Ages 13–15: 2020, 2020.5 COVID, 2021 Ages 16–18: 2018 and 2020 Five level response from 2021 onwards (only ages 13+) Q: What is your gender? A: Male, Female, Non-binary, Other, Don’t know Ages 13–15: 2022 and 2023 Ages 16–18: 2021 LIFECOURSE (longitudinal): Used binary (boy or girl) options for 2017–2018 and three level option 2019–2020. As longitudinal we can monitor changes in response option within participant and compare against sex assigned at birth.
Questionnaire availability	Upon request
Language versions of the questionnaire	Icelandic, English and Polish (latter in more recent years)
LGBTI+ -related reporting	Sigurvinsdottir, R., Gisladottir, B., Asgeirsdottir, B. B., & Sigfusdottir, I. D. (2024). Sexual attraction and non-suicidal self-harm: the role of stressors and psychological mediators. Archives of sexual behavior, 53(4), 1293–1306.
Homepage	Rannsoknir.is
References	Halldorsdottir, Thorhildur, Alfgeir Logi Kristjansson, Bryndis Bjork Asgeirsdottir, Ingibjorg Eva Thorisdottir, Jon Sigfusson, Erla Maria Jonsdottir Tolgyes, Heiddis B. Valdimarsdottir, John Allegrante, and Inga Dora Sigfusdottir. A multi-level developmental approach towards understanding adolescent mental health and behaviour: Rationale, design and methods of the LIFECOURSE study in Iceland. Social Psychiatry and Psychiatric Epidemiology 56, no. 3 (2021): 519–529. Haskell, E., Sigmarsdottir, B., Thorisdottir, I. E., Valborgarson, A., Aparicio, E. B., Kiviruusu, O., ... & Halldorsdottir, T. (2025). Adolescent mental health before, during, and after the COVID-19 pandemic in Iceland: A repeated, cross-sectional, population-based study. The Lancet Regional Health–Europe, 53. Thorisdottir, I. E., Asgeirsdottir, B. B., Kristjansson, A. L., Valdimarsdottir, H. B., Tolgyes, E. M. J., Sigfusson, J., ... & Halldorsdottir, T. (2021). Depressive symptoms, mental wellbeing, and substance use among adolescents before and during the COVID-19 pandemic in Iceland: A longitudinal, population-based study. The Lancet Psychiatry, 8(8), 663–672.

Ungdata
Country	Norway
Target group	Lower and upper secondary school students (ages 13–19)
First data collection	2010
Data collection frequency	Usually every 3 years per municipality (e.g., the survey completed data collected in all of Norway through 2023, 2024 and 2025)
Contact information	anders.bakken@oslomet.no
LGBTI+-related questions in the survey	Since 2023: “There is a diversity of sexual orientations. Which of the following fits you best?” Responses included Heterosexual Gay/lesbian Bisexual Other (for example pansexual, queer, asexual, fluid) Unsure/still figuring it out Don’t want to answer
Questionnaire availability	Available to researchers in Norway through Sikt: https://doi.org/10.18712/NSD-NSD3157-V1
Language versions of the questionnaire	Norwegian, English
LGBTI+-related reporting	Not published yet
Homepage	https://www.ungdata.no/english/
References	Enstad, F., Helseth, S., Løyland, B., Haraldstad, K., & Skarstein, S. O. (2025). Use of over-the-counter analgesics in Norwegian children – a national cross-sectional study. Scandinavian Journal of Public Health. https://doi.org/10.1177/14034948251328492 Grasaas, E., Ostojic, S., & Sandbakk, Ø. (2024). Associations between levels of physical activity and satisfaction with life among Norwegian adolescents: a cross-sectional study. Frontiers in Sports and Active Living, 6. https://doi.org/10.3389/fspor.2024.1437747 Lien, L., Bonsaksen, T., Stea, T. H., Kleppang, A. L., Steigen, A. M., & Leonhardt, M. (2023). Time trends in self-reported depressive symptoms, prescription of antidepressants, sedatives and hypnotics and the emergence of social media among Norwegian adolescents. PLoS ONE, 18(12), e0295384. https://doi.org/10.1371/journal.pone.0295384 Myhr, A., Vesterbekkmo, R. K., Samarawickrema, I., & Sund, E. R. (2024). Trends in Norwegian adolescents’ substance use between 2014 and 2022: socioeconomic and gender differences. BMC Public Health, 24(1). https://doi.org/10.1186/s12889-024-19983-9 Yu, B., Von Soest, T., & Nes, R. B. (2023). Do municipal contexts matter for adolescent mental health? A Within-Municipality analysis of nationwide Norwegian survey data across six years. Research on Child and Adolescent Psychopathology, 52(2), 169–182. https://doi.org/10.1007/s10802-023-01123-3

The National Public Health Survey
Country	Sweden
Target group	16 and older
First data collection	2004
Data collection frequency	Every second year (with some exceptions)
Contact information	folkhalsoenkaten@folkhalsomyndigheten.se
LGBTI+-related questions in the survey	Gender identity (female, male, non-binary, wish not to categorise myself, not sure) 2018 Are you, or have you been, a transperson? A transperson has a gender identity and/or a gender expression that does not correspond to the legal sex assigned at birth. For example, someone who is born and raised as a woman but feels more like a man. (yes, no, not sure) 2015 How would you define your sexual identity? Select only one option. If several options apply, mark the one that best applies. (heterosexual, homosexual, bisexual, pansexual, asexual, other, not sure) (2005) 2008
Questionnaire availability	Available at www.folkhalsomyndigheten.se
Language versions of the questionnaire	Swedish, English
LGBTI+-related reporting	https://www.folkhalsomyndigheten.se/publikationer-och-material/publikationsarkiv/l/livsvillkor-levnadsvanor-och-halsa-hos-aldre-homosexuella-bisexuella-och-transpersoner/ https://www.folkhalsomyndigheten.se/publikationer-och-material/publikationsarkiv/u/utvecklingen-av-halsan-och-halsans-bestamningsfaktorer-bland-homo--och-bisexuella-personer-resultat-fran-nationella-folkhalsoenkaten-halsa-pa-lika-villkor/

SHILD (Survey of Health, Impairment and Living Conditions) survey
Country	Denmark
Target group	Individuals aged 16–64
First data collection	SHILD (Survey of Health, Impairment and Living Conditions in Denmark) is a panel survey with particular focus on living conditions and disability in Denmark as well as physical and mental health and has been widely used to study health and living conditions across different population groups. The survey is based on online questionnaires with follow-up by phone. Each wave covers approximately 35,000 individuals aged 16–64, with a response rate of around 50% across all three waves. The first questionnaire was distributed in 2012, but questions on sexual orientation and gender identity were not included until 2020. The 2020 data collection took place between 9 September and 22 November 2020 and covered individuals aged 16–64 as of 1 September 2020. Participants were invited to the survey via the predominant digital postbox solution in Denmark (e-Boks), or by letter if they were exempt from digital communication, with follow-up conducted by phone. Data collection was therefore a combination of web-based responses and telephone interviews. In total, 17,935 complete responses were collected. Out of the 38,000 individuals sampled, this corresponds to a response rate of 47.2%. Same procedure is used in the upcoming roll-out of the survey this fall (2025).
Data collection frequency	Every four years (as far as possible)
Contact information	jagr@vive.dk
LGBTI+-related questions in the survey	In 2020 and in 2025: “How would you describe your sexual orientation?” Homosexual Bisexual Heterosexual Asexual None of the above. Please specify: _____ Prefer not to answer In 2020: “In Denmark, everyone is assigned a sex at birth: either male or female. Not everyone identifies with the sex they were assigned. Do you identify with the sex you were assigned at birth?” No, I identify with a different gender than the sex I was assigned at birth Yes, I identify with the sex I was assigned at birth Other. Please specify: _____ Prefer not to answer In 2025: “What sex were you assigned at birth? For example, the sex listed on your birth certificate” Female Male Prefer not to answer In 2025: “Which of the following best describes your gender identity? The gender you identify with today” Female Male Non-binary Other. Please specify: _____ Prefer not to answer
Questionnaire availability	The distributed questionnaires are available upon request.
Language versions of the questionnaire	Danish
LGBTI+-related reporting	Danish and English for SHILD 2020. Not published yet for SHILD 2025.
Homepage	SHILD (Survey of Health, Impairment and Living Conditions in Denmark) - vive.dk
References	Greve, Jane, Østergaard, Stine V., Andersen, Matvei, Thomsen, Morten K. (2022). Kortlægning af homo- og biseksuelles samt transpersoners levevilkår og samfundsdeltagelse. København: VIVE – Det Nationale Forsknings- og Analysecenter for Velfærd. En kortlægning af homo- og biseksuelles samt transpersoners levevilkår og samfundsdeltagelse Thomsen, Morten K., Andersen, Matvei, Greve, Jane (2024). Transgender lives at the population level: Evidence from Danish administrative data. Social Science & Medicine, 358(2024):117182. doi:10.1016/j.socscimed.2024.117182 Greve, Jane, Frøslev-Thomsen, Josefine, Andersen, Matvei (2023). LGBT+familier med tre eller fire forældre – Karakteristik af LGBT+familier og en beskrivelse af de udfordringer, som LGBT+familier med tre eller fire forældre oplever. København: VIVE – Det Nationale Forsknings- og Analysecenter for Velfærd. LGBT+familier med tre eller fire forældre

SHILD-TRALE (Survey of Health, Impairment and Living Conditions – Transgender Lives and Experience) survey
Country	Denmark
Target group	Individuals that changed their legal gender between 2000 and 2021
First data collection	SHILD-TRALE is a spin-off survey to SHILD collected by VIVE in 2021/2022, referring to Transgender Lives and Experience Survey. The questionnaire uses selected questions from the SHILD survey, supplemented with questions specifically about having a gender identity or gender expression different from the sex they were assigned at birth. The Danish Health Data Authority carried out a CPR selection for VIVE covering all individuals in Denmark who had changed their legal gender (registered as a change in the last digit of their CPR number) between 2000 and 2021. Every individual residing in Denmark is assigned a unique 10-digit Central Personal Register (CPR) number. The first six digits denote the birth date (day, month, year without the century), while the last four form a sequence number, with the final digit indicating the sex of the individual – even number for females, odd for males. According to The Danish Health Data Authority, 2,131 individuals had undergone a legal gender change between 2000 and 2021, of these, 1,833 individuals were between the ages 18–64 as of September 2020, set as the age restriction for the further analyses. Respondents were invited to participate via e-Boks, where they also received up to two reminders about the survey. Data collection was carried out as an online survey and the questionnaire was conducted between 22 December 2021 and 9 February 2022. 849 respondents fully completed the questionnaire, corresponding to a response rate of 46.3%.
Data collection frequency	Once in 2021/2022
Contact information	JaGr@vive.dk
LGBTI+ -related questions in the survey	The purpose of the survey is to shed light on the living conditions and social participation of transgender people in Denmark. In this context, the term ‘transgender’ is used as an umbrella term for people who, to varying degrees, do not identify with the sex they were assigned at birth. All respondents are considered transgender, as they have undergone a legal gender change. Consequently, all questions are LGBTI+ related and relevant.
Questionnaire availability	The distributed questionnaire is available upon request.
Language versions of the questionnaire	Danish
LGBTI+-related reporting	Danish
Homepage	https://www.vive.dk/da/udgivelser/kortlaegning-af-homo-og-biseksuelles-samt-transpersoners-levevilkaar-og-samfundsdeltagelse-0xgel1vk/
References	Greve, Jane, Østergaard, Stine V., Andersen, Matvei, Thomsen, Morten K. (2022). Kortlægning af homo- og biseksuelles samt transpersoners levevilkår og samfundsdeltagelse. København: VIVE – Det Nationale Forsknings- og Analysecenter for Velfærd. En kortlægning af homo- og biseksuelles samt transpersoners levevilkår og samfundsdeltagelse Steffensen, Tinne, Kroustrup, Johannes (2023). LGBT+ barometer. København: Institut for Menneskerettigheder. LGBT+ barometer \| Institut for Menneskerettigheder

Young in 2023 – Is There Space for Everyone? survey
Country	Denmark
Target group	Individuals aged 15–25
First data collection	The survey data was collected between 25 April and 26 June 2023. The questionnaire was distributed to a random sample of 15–25-year-olds living in Denmark, with a 20% selection from each birth year within this age group as of 1 January 2023. The sample was random within each cohort and therefore not dependent on sex, ethnicity, education, or other characteristics. Respondents were invited to participate via Digital Mail, and the questionnaire could only be accessed through this platform. For participants under the age of 18, their parents were informed about the study in an informational letter sent to their own Digital Mail. At the same time as the survey was distributed, the study was also announced on Facebook and LinkedIn. To further increase the response rate, ten gift cards of 1,000 Danish kroner were awarded by lottery. In total, 31,420 individuals responded, of whom 27,493 completed the questionnaire in full, corresponding to a response rate of 19.6%.
Data collection frequency	Once in 2023
Contact information	JaGr@vive.dk
LGBTI+-related questions in the survey	“Not everyone identifies with the sex assigned to them at birth. Do you identify with the sex you were assigned at birth?” Yes, I identify with the sex I was assigned at birth No, I do not identify with the sex I was assigned at birth I am not undecided Prefer not to answer “How would you describe your gender identity?” Non-binary Male Female I am undecided Prefer not to answer A different gender identity. Please specify:_____ “How old were you, when you first became aware of having a gender identity different from the sex you were assigned at birth? If you do not remember exactly, please provide your best estimate” (List of ages) “How old were you, when you first began talking to someone about having a gender identity different from the sex you were assigned at birth? If you do not remember exactly, please provide your best estimate” (List of ages) “Are you open about your gender identity at your school?” I am open about it with everyone at my school I am open about it with most I am open about it with a few No, I am not open about it at my school Don’t know/prefer not to answer “Who at your school are you open about it with? (you can mark more than one option)” My classmates The staff at school Other students at school Others Don’t know/prefer not to answer “Why are you not open about it at your school? (you can mark more than one option)” I know that they would not understand it I think that they would not accept me I think that it will make my life more difficult I feel that the school is an unsafe place to be open I think that my teacher(s) will bully me I think that the other students will bully me I am undecided/in doubt about my gender identity I am ashamed about my gender identity I do not feel the need to be open about my gender identity I am worried that someone will tell it to my parent(s) Other Don’t know/prefer not to answer “What is your sexual orientation? (Your sexual orientation is about your sexual attraction to other people)” Heterosexual Homosexual Bi- or pansexual Asexual I am undecided Prefer not to answer Other sexual orientation. Please specify: ______ “How old were you, when you first became aware of your sexual orientation? If you do not remember exactly, please provide your best estimate” (List of ages) “How old were you, when you first began talking to someone about your sexual orientation? If you do not remember exactly, please provide your best estimate” (List of ages) “Are you open about your sexual orientation at your school?” I am open about it with everyone at my school I am open about it with most I am open about it with a few No, I am not open about it at my school Don’t know/prefer not to answer “Who at your school are you open about it with? (you can mark more than one option)” My classmates The staff at school Other students at school Others Don’t know/prefer not to answer “Why are you not open about it at your school? (you can mark more than one option)” I know that they would not understand it I think that they would not accept me I think that it will make my life more difficult I feel that the school is an unsafe place to be open I think that my teacher(s) will bully me I think that the other students will bully me I am undecided/in doubt about my sexual orientation I am ashamed about my sexual orientation I do not feel the need to be open about my sexual orientation I am worried that someone will tell it to my parent(s) Other Don’t know/prefer not to answer “Which of the following statements best match your own perception of your sexual orientation? (you can mark more than one option)” I feel good about my sexual orientation I am proud of my sexual orientation I am sad about my sexual orientation I am ashamed of my sexual orientation Other Don’t know/prefer not to answer “Which of the following statements best match your own perception of your gender identity? (you can mark more than one option)” I feel good about my gender identity I am proud of my gender identity I am sad about my gender identity I am ashamed of my gender identity Other Don’t know/prefer not to answer “How much do you agree or disagree with the following statement about your work experience placement/internship: “I experience that I can be honest about my gender identity at my placement” Totally agree Agree Neither agree nor disagree Disagree Totally disagree Don’t know/prefer not to answer “I experience that I can be honest about my sexuality at my placement” Totally agree Agree Neither agree nor disagree Disagree Totally disagree Don’t know/prefer not to answer Battery/survey-experiment about perceptions of diversity and inclusion at school. Questions related to scenarios with different gender identities or sexual orientations in school settings. “Does your school have clear rules on appropriate behavior concerning the use of offensive language and bullying based on gender identity and/or sexual orientation?” Yes, and the rules are respected Yes, but the rules are not respected No Don’t know/prefer not to answer “Have you experienced that words like ‘faggot’, ‘gay’, ‘lesbian’, ‘homo’ or similar are being used as slurs at your school?” Every day Once or twice a week Once or twice a month Once or twice Not at all Don’t know/prefer not to answer “To what degree do you feel comfortable telling your teachers if you experience challenges related to your sexual orientation?” To a very high degree To a high degree To some degree To a lower degree Not at all Don’t know/prefer not to answer “To what degree do you feel comfortable telling your teachers if you experience challenges related to your gender identity?” To a very high degree To a high degree To some degree To a lower degree Not at all Don’t know/prefer not to answer “Have you experienced any unpleasant incidents, bullying, harassment, or violence based on your gender identity and/or gender expression at school or in your education? (you can mark more than one option)” Yes, unwanted or over-the-top attention to my gender identity and/or gender expression Yes, my appearance and/or gender has been commented on in a way I found uncomfortable or offensive Yes, a lack of recognition of my gender identity and/or gender expression Yes, faced with assumptions that people with my gender identity and/or gender expression does not exist Other forms of bullying/harassment or violence No, I have not experienced any uncomfortable experiences, bullying, violence or harassment because of my gender identity and/or gender expression Don’t know/prefer not to answer “Have you experienced any unpleasant incidents, bullying, harassment, or violence based on your sexual orientation at school or in your education? (you can mark more than one option)” Yes, unwanted or over-the-top attention to my sexual orientation Yes, my sexuality has been commented on in a way I found uncomfortable or offensive Yes, a lack of recognition of my sexual orientation Yes, faced with assumptions that people with my sexual orientation does not exist Other forms of bullying/harassment or violence No, I have not experienced any uncomfortable experiences, bullying, violence or harassment because of my sexual orientation Don’t know/prefer not to answer
Questionnaire availability	The distributed questionnaire is available upon request.
Language versions of the questionnaire	Danish
LGBTI+ -related reporting	Summary reports in Danish
Homepage	LGBT+-elevers trivsel og mentale sundhed samt oplevelser af mobning, vold, chikane og diskrimination - vive.dk
References	Greve, Jane, Andersen, Didde B., Nicholajsen, Julie S., Kolodziejczyk, Christophe (2024). LGBT+-elevers trivsel og mentale sundhed samt oplevelser af mobning, vold, chikane og diskrimination – En kortlægning for grundskolen, ungdomsuddannelserne og FGU-institutionerne. København: VIVE – Det Nationale Forsknings- og Analysecenter for Velfærd. LGBT+-elevers trivsel og mental sundhed samt oplevelser af mobning, vold, chikane og diskrimination Andersen, Didde B., Kolodziejczyk, Christophe, Greve, Jane (2024). Trivsel og mental sundhed blandt LGBT+-unge – En kortlægning for udvalgte områder i Danmark. København: VIVE – Det Nationale Forsknings- og Analysecenter for Velfærd. Trivsel og mental sundhed blandt LGBT+-unge – En kortlægning af trivsel og mental sundhed samt oplevelse af accept, tryghed og regler for god opførsel for udvalgte områder i Danmark Langt større mistrivsel blandt LGBT+-unge” [In English: Markedly Higher Mental Health Challenges Among LGBT+ Youth] (with Didde B. Andersen and Christophe Kolodziejczyk). Unge Pædagoger (4) 2024.

School Health Promotion study
Country	Finland
Target group	Children and adolescents
First data collection	Data have been collected from 8th and 9th graders in comprehensive schools since 1996, in upper secondary schools since 1999 and in vocational institutions since 2008. Children attending the 4th and 5th grades in comprehensive schools were included in 2017.
Data collection frequency	Biennially; most recent 2025
Contact information	kouluterveyskysely@thl.fi
LGBTI+-related questions in the survey	Sexual orientation since 2017, Gender identity since 2019 What is your official gender? Boy Girl What gender do you identify as? Boy Girl Both Neither It varies Which of the following best describes your sexual orientation at this moment? Straight Bisexual or pansexual Gay None of these options describe me Not sure
Questionnaire availability	Available at the survey’s webpages
Language versions of the questionnaire	Finnish, Swedish, English, Russian, Northern Sámi
LGBTI+-related reporting	Summary reports in Finnish
Homepage	Finnish: https://thl.fi/kouluterveyskysely Swedish: https://thl.fi/sv/forskning-och-utveckling/undersokningar-och-projekt/enkaten-halsa-i-skolan English: https://thl.fi/en/research-and-development/research-and-projects/school-health-promotion-study
References	Well-being of children and young people – School Health Promotion study 2023. Statistical report 50/2023, 21.9.2023. THL. https://thl.fi/en/statistics-and-data/statistics-by-topic/social-services-children-adolescents-and-families/well-being-of-children-and-young-people-school-health-promotion-study Quality description https://thl.fi/en/statistics-and-data/data-and-services/quality-and-statistical-principles/quality-descriptions/well-being-of-children-and-young-people-school-health-promotion-study Lehtonen J, Majlander S, Sares-Jäske L, Jehkoi A, Luopa P. Sukupuoli- ja seksuaalivähemmistöihin kuuluvien 8.-ja 9.-luokkalaisten hyvinvointi – Kouluterveyskysely 2019–2023. Tutkimuksesta tiiviisti 13/2024. Terveyden ja hyvinvoinnin laitos, Helsinki https://urn.fi/URN:ISBN:978-952-408-279-2 Sares-Jäske L, Czimbalmos M, Majlander S, Siukola R, Klemetti R, Luopa P, Lehtonen J. Gendered Differences in Experiences of Bullying and Mental Health Among Transgender and Cisgender Youth. J Youth Adolesc. 2023 Aug;52(8):1531–1548. Kiviruusu O, Ranta K, Lindgren M, Haravuori H, Silén Y, Therman S, Lehtonen J, Sares-Jäske L, Aalto-Setälä T, Marttunen M, Suvisaari J. Mental health after the COVID-19 pandemic among Finnish youth: A repeated, cross-sectional, population-based study. Lancet Psychiatry. 2024 Jun;11(6):451–460

Healthy Finland Survey
Country	Finland
Target group	people aged 20 years and over
First data collection	2022
Data collection frequency	The Healthy Finland survey consists of different surveys which vary from year to year. In even-numbered years, a large-scale questionnaire survey is carried out to assess health, well-being and use of services, among other things. Every six years, the Healthy Finland Survey collects data for the European Health Interview Survey (EHIS). Every six years, the survey is accompanied by a comprehensive health check.
Contact information	tervesuomi@thl.fi
LGBTI+-related questions in the survey	Since 2022: “Do you belong to a gender minority or sexual minority?” no a gender minority (such as trans people or intersex people) a sexual minority (such as gay men, lesbians, bisexuals, pansexuals or asexuals)
Questionnaire availability	Available at the survey’s webpages
Language versions of the questionnaire	Finnish, Swedish, English, Russian
LGBTI+-related reporting	Not published yet
Homepage	https://thl.fi/tutkimus-ja-kehittaminen/tutkimukset-ja-hankkeet/terve-suomi-tutkimus https://thl.fi/sv/forskning-och-utveckling/undersokningar-och-projekt/undersokningen-halsosamma-finland https://thl.fi/en/research-and-development/research-and-projects/healthy-finland-survey
References	Sääksjärvi K, Elonheimo HM, Ikonen J, Lehtoranta L, Parikka S, Härkänen T, Vihervaara T, Sainio P, Jääskeläinen T, Suominen AL, Harjunmaa U, Mäkelä P, Lahti J, Kaartinen NE, Koskinen S, Lundqvist A. Cohort Profile: Healthy Finland Survey. Int J Epidemiol. 2024;54(1):dyae166. doi: 10.1093/ije/dyae166.