Ralf Kuja-Halkola
Om mig
Forskare och statistiker på Institutionen för Medicinsk Epidemiologi och Biostatistik (http://ki.se/meb) och Svenska Tvillingregistret (http://ki.se/forskning/svenska-tvillingregistret).
Forskningsbeskrivning
Registerbaserad forskning i Borderline personlighetsstörning
Jag leder en bredare undersökning av Borderline personlighetsstörning, dess orsaker, komorbiditeter, konsekvenser, och farmakologiskt behandling. Vi nyttjar de omfattande populationsregistren i Sverige för att undersöka associationer och hypoteser i den största gruppen med Borderline personlighetsstörningsdiagnos som någonsin studerats.
Psykiatrisk epidemiologi
Jag är inblandad i undersökningar av bland annat ADHD, autism, och ångest i Henrik Larsson (https://ki.se/people/henlar) och Paul Lichtensteins (https://ki.se/people/paulic) forskargrupper. Jag samarbetar med forskargrupper inom psykiatrisk epidemiologi på Institutionen för Medicinsk Epidemiologi och Biostatistik i en grupp som heter PsychEpi.
Undervisning
Jag är kursansvarig för kursen "Design and Analysis of Twin- and Family-based studies" som ges inom ramen för doktorandprogrammet i epidemiologi.
Artiklar
- Article: BIOLOGICAL PSYCHIATRY. 2024;96(11):868-875
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2024;65(12):1590-1600
- Article: MOLECULAR PSYCHIATRY. 2024;:1-6
- Article: BMJ MENTAL HEALTH. 2024;27(1):e301203
- Article: JOURNAL OF INTERNAL MEDICINE. 2024;296(4):336-349
- Article: CNS DRUGS. 2024;38(10):827-838
- Article: BMJ MENTAL HEALTH. 2024;27(1):e301195
- Article: BIOLOGICAL PSYCHIATRY. 2024;:S0006-3223(24)01587-7
- Article: SCIENTIFIC REPORTS. 2024;14(1):21143
- Article: INFLAMMATORY BOWEL DISEASES. 2024;30(9):1556-1565
- Article: COMMUNICATIONS BIOLOGY. 2024;7(1):1077
- Article: JCPP ADVANCES. 2024;4(3):e12238
- Article: PSYCHIATRY RESEARCH. 2024;339:115990
- Article: JAMA PSYCHIATRY. 2024
- Article: JAMA PSYCHIATRY. 2024;81(8):747-748
- Article: SCHIZOPHRENIA BULLETIN. 2024;50(4):881-890
- Article: AMERICAN JOURNAL OF PSYCHIATRY. 2024;181(7):651-657
- Article: JCPP ADVANCES. 2024;4(2):e12225
- Article: AGING CELL. 2024;23(6):e14135
- Article: JAMA PSYCHIATRY. 2024;81(6):586-594
- Article: THE LANCET DIABETES AND ENDOCRINOLOGY. 2024;12(5):320-329
- Article: JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION (JAMA). 2024;331(10):850-860
- Article: JAMA PSYCHIATRY. 2024;81(3):284-291
- Article: JAMA PSYCHIATRY. 2024;81(2):178-187
- Article: THE BMJ. 2024;384:e077564
- Article: PLOS ONE. 2024;19(3):e0297639
- Article: PLOS ONE. 2024;19(8):e0308254
- Article: JAMA PSYCHIATRY. 2024;81(1):25-33
- Journal article: OBSTETRIC ANESTHESIA DIGEST. 2023;43(4):207-208
- Article: JCPP ADVANCES. 2023;3(4):e12179
- Article: TRANSLATIONAL PSYCHIATRY. 2023;13(1):366
- Article: PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. BIOLOGICAL SCIENCES. 2023;290(2009):20231888
- Article: JAMA NETWORK OPEN. 2023;6(10):e2336621
- Article: AMERICAN JOURNAL OF PSYCHIATRY. 2023;180(10):714-722
- Article: ALCOHOL: CLINICAL AND EXPERIMENTAL RESEARCH. 2023;47(9):1677-1689
- Article: ECLINICALMEDICINE. 2023;63:102170
- Article: SCIENTIFIC REPORTS. 2023;13(1):13124
- Article: ARTHRITIS & RHEUMATOLOGY. 2023;75(8):1445-1455
- Article: MOVEMENT DISORDERS. 2023;38(8):1419-1427
- Article: AGING CELL. 2023;22(8):e13868
- Article: BRITISH JOURNAL OF CANCER. 2023;129(1):94-103
- Article: CIRCULATION. 2023;148(3):256-267
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2023;64(7):1027-1036
- Article: THE LANCET. HEALTHY LONGEVITY. 2023;4(7):e307-e315
- Article: BMC PSYCHIATRY. 2023;23(1):442
- Article: THE LANCET PUBLIC HEALTH. 2023;8(6):e432-e441
- Article: GEROSCIENCE. 2023;45(3):2051-2064
- Article: PSYCHOLOGICAL MEDICINE. 2023;53(7):3096-3104
- Article: JAMA NETWORK OPEN. 2023;6(4):e238135
- Article: PSYCHOLOGICAL MEDICINE. 2023;53(4):1510-1517
- Article: THE JOURNALS OF GERONTOLOGY. SERIES A, BIOLOGICAL SCIENCES AND MEDICAL SCIENCES. 2023;78(2):333-341
- Article: JOURNAL OF INTERNAL MEDICINE. 2023;293(2):200-211
- Article: AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY. 2023;228(2):233.e1-233.e12
- Article: BMC MEDICINE. 2023;21(1):9
- Article: GERONTOLOGY. 2023;69(4):396-405
- Article: PSYCHOLOGICAL MEDICINE. 2023;53(2):371-378
- Article: AMERICAN JOURNAL OF MEDICAL GENETICS, PART B: NEUROPSYCHIATRIC GENETICS. 2023;192(1-2):3-12
- Article: FRONTIERS IN ONCOLOGY. 2023;13:928008
- Article: PLOS MEDICINE. 2023;20(1):e1004164
- Article: JAMA PSYCHIATRY. 2022;79(12):1188-1198
- Article: DIABETES CARE. 2022;45(12):2950-2956
- Article: EUROPEAN JOURNAL OF PUBLIC HEALTH. 2022;32(6):933-938
- Article: THE JOURNALS OF GERONTOLOGY. SERIES A, BIOLOGICAL SCIENCES AND MEDICAL SCIENCES. 2022;77(11):2311-2319
- Article: TRANSLATIONAL PSYCHIATRY. 2022;12(1):488
- Article: AMERICAN JOURNAL OF PSYCHIATRY. 2022;179(11):824-832
- Article: ACTA PAEDIATRICA, INTERNATIONAL JOURNAL OF PAEDIATRICS. 2022;111(11):2131-2141
- Article: ACTA PSYCHIATRICA SCANDINAVICA. 2022;146(4):370-380
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2022;63(9):1092-1102
- Article: DIABETES CARE. 2022;45(9):1987-1993
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2022;63(8):921-928
- Article: HUMAN BRAIN MAPPING. 2022;43(11):3508-3523
- Article: JOURNAL OF THE AMERICAN ACADEMY OF CHILD AND ADOLESCENT PSYCHIATRY. 2022;61(7):934-945
- Article: JOURNAL OF CRIMINAL JUSTICE. 2022;81:101920
- Article: INTERNATIONAL JOURNAL OF EPIDEMIOLOGY. 2022;51(3):898-909
- Article: JAMA NETWORK OPEN. 2022;5(6):e2214779
- Article: PSYCHIATRY RESEARCH. 2022;312:114556
- Article: EUROPEAN JOURNAL OF ENDOCRINOLOGY (EJE). 2022;186(6):677-685
- Article: ALZHEIMER'S AND DEMENTIA. 2022;18(6):1155-1163
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2022;63(5):591-598
- Article: MOLECULAR PSYCHIATRY. 2022;27(5):2514-2521
- Article: EUROPEAN CHILD AND ADOLESCENT PSYCHIATRY. 2022;31(5):829-839
- Article: BMC PSYCHIATRY. 2022;22(1):233
- Article: CLINICAL NUTRITION ESPEN. 2022;48:186-195
- Article: TRANSLATIONAL PSYCHIATRY. 2022;12(1):95
- Article: MOLECULAR PSYCHIATRY. 2022;27(3):1667-1675
- Article: PSYCHOLOGICAL MEDICINE. 2022;52(3):496-505
- Article: BRAIN, BEHAVIOR, AND IMMUNITY. 2022;99:247-255
- Article: JOURNAL OF CRIMINAL JUSTICE. 2022;78:101879
- Article: JOURNAL OF THE AMERICAN HEART ASSOCIATION. 2021;10(23):e022264
- Article: JCPP ADVANCES. 2021;1(4):e12044
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2021;62(11):1274-1284
- Article: ANNALS OF THE RHEUMATIC DISEASES. 2021;80(11):1461-1466
- Article: JOURNAL OF CLINICAL ENDOCRINOLOGY AND METABOLISM (JCEM). 2021;106(11):e4459-e4470
- Article: BMC MEDICINE. 2021;19(1):248
- Article: MOLECULAR PSYCHIATRY. 2021;26(9):5389-5397
- Article: THE LANCET PSYCHIATRY. 2021;8(9):774-783
- Article: JOURNAL OF BONE AND JOINT SURGERY. AMERICAN VOLUME. 2021;103(14):1319-1327
- Article: AGING. 2021;13(13):16990-17023
- Article: MOLECULAR PSYCHIATRY. 2021;26(7):3201-3209
- Article: INTERNATIONAL JOURNAL OF EATING DISORDERS. 2021;54(6):925-935
- Article: JOURNAL OF CLINICAL PERIODONTOLOGY. 2021;48(6):756-764
- Article: JOURNAL OF THE AMERICAN ACADEMY OF CHILD AND ADOLESCENT PSYCHIATRY. 2021;60(5):593-603
- Article: PEDIATRIC ALLERGY AND IMMUNOLOGY. 2021;32(4):709-719
- Article: JOURNAL OF THE AMERICAN GERIATRICS SOCIETY. 2021;69(5):1128-1139
- Article: DIABETES CARE. 2021;44(5):1143-1150
- Article: DIABETOLOGIA. 2021;64(4):767-777
- Article: MOLECULAR PSYCHIATRY. 2021;26(4):1224-1233
- Article: PSYCHIATRY RESEARCH. 2021;298:113794
- Article: PSYCHOLOGICAL MEDICINE. 2021;51(5):861-869
- Article: JOURNAL OF CLINICAL ENDOCRINOLOGY AND METABOLISM (JCEM). 2021;106(4):1101-1110
- Article: JOURNAL OF UROLOGY. 2021;205(3):864-870
- Article: JAMA PSYCHIATRY. 2021;78(3):302-310
- Article: MOLECULAR PSYCHIATRY. 2021;26(3):974-985
- Article: JAMA NETWORK OPEN. 2021;4(3):e210837
- Article: MOLECULAR PSYCHIATRY. 2021;26(3):999-1008
- Article: EVOLUTION AND HUMAN BEHAVIOR. 2021;42(2):157-164
- Article: JOURNAL OF ATTENTION DISORDERS. 2021;25(3):312-321
- Article: PLOS ONE. 2021;16(8):e0256250
- Article: PSYCHOLOGICAL MEDICINE. 2021;51(1):62-69
- Article: MOLECULAR PSYCHIATRY. 2021;26(1):341-349
- Article: THE BRITISH JOURNAL OF PSYCHIATRY. SUPPLEMENT. 2021;218(1):35-42
- Journal article: THE LANCET PSYCHIATRY. 2021;8(9):774-783
- Article: SCIENTIFIC REPORTS. 2020;10(1):22417
- Article: JAMA NETWORK OPEN. 2020;3(12):e2028477
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2020;61(12):1370-1379
- Article: AMERICAN JOURNAL OF MEDICAL GENETICS, PART B: NEUROPSYCHIATRIC GENETICS. 2020;183(8):475-485
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2020;61(9):959-968
- Journal article: ENDOCRINE ABSTRACTS. 2020
- Article: MOLECULAR PSYCHIATRY. 2020;25(8):1809-1821
- Article: MICROORGANISMS. 2020;8(8):E1126-1126
- Article: PSYCHOLOGICAL MEDICINE. 2020;50(10):1706-1715
- Article: JAMA PSYCHIATRY. 2020;77(7):715-728
- Article: SOCIAL COGNITIVE AND AFFECTIVE NEUROSCIENCE. 2020;15(4):423-436
- Article: TRANSLATIONAL PSYCHIATRY. 2020;10(1):173
- Article: EUROPEAN JOURNAL OF ENDOCRINOLOGY (EJE). 2020;182(5):473-480
- Article: AMERICAN JOURNAL OF MEDICAL GENETICS, PART A. 2020;182(5):1177-1189
- Article: CANCER RESEARCH. 2020;80(7):1590-1600
- Article: JOURNAL OF DENTAL RESEARCH. 2020;99(3):264-270
- Article: PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. BIOLOGICAL SCIENCES. 2020;287(1921):20192849
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2020;61(2):140-147
- Article: ADDICTION. 2020;115(2):326-336
- Article: MOLECULAR AUTISM. 2020;11(1):1
- Article: PLOS ONE. 2020;15(4):e0230389
- Article: PSYCHIATRY RESEARCH. 2019;282:112566
- Article: BMC PSYCHIATRY. 2019;19(1):363
- Article: AMERICAN SOCIETY OF NEPHROLOGY. CLINICAL JOURNAL. 2019;14(11):1590-1596
- Article: JAMA PSYCHIATRY. 2019;76(11):1141-1149
- Article: JOURNAL OF PSYCHOSOMATIC RESEARCH. 2019;126:109797
- Article: BIOLOGICAL PSYCHIATRY. 2019;86(8):577-586
- Article: PSYCHIATRY RESEARCH. 2019;278:180-187
- Article: PSYCHOLOGICAL MEDICINE. 2019;49(11):1841-1849
- Article: JOURNAL OF AUTISM AND DEVELOPMENTAL DISORDERS. 2019;49(7):2838-2848
- Article: PSYCHOLOGICAL MEDICINE. 2019;49(10):1713-1721
- Article: INTERNATIONAL JOURNAL OF EPIDEMIOLOGY. 2019;48(3):926-933
- Article: SCIENTIFIC REPORTS. 2019;9(1):7554
- Article: KIDNEY INTERNATIONAL. 2019;95(5):1225-1233
- Journal article: JOURNAL OF THE ENDOCRINE SOCIETY. 2019;3(Supplement_1):or19-or11
- Article: CHINESE JOURNAL OF EPIDEMIOLOGY. 2019;40(4):389-393
- Journal article: JOURNAL OF THE ENDOCRINE SOCIETY. 2019;3(Suppl 1)OR19-1 Heritability and Etiological Overlap in Seven Autoimmune Diseases: A Population-Based Swedish Twin Study
- Article: JOURNAL OF THE AMERICAN ACADEMY OF CHILD AND ADOLESCENT PSYCHIATRY. 2019;58(4):423-432
- Article: JAMA NEUROLOGY. 2019;76(4):454-461
- Article: CEREBRAL CORTEX. 2019;29(3):1342-1350
- Article: EBIOMEDICINE. 2019;40:710-716
- Article: EPILEPSIA. 2019;60(2):284-293
- Article: MOLECULAR AUTISM. 2019;10(1):45
- Article: PSYCHOLOGICAL MEDICINE. 2018;48(16):2740-2747
- Article: BIOLOGICAL PSYCHIATRY. 2018;84(11):810-816
- Article: JAMA NEUROLOGY. 2018;75(9):1098-1105
- Article: JOURNAL OF AUTISM AND DEVELOPMENTAL DISORDERS. 2018;48(9):3244-3252
- Article: EUROPEAN EATING DISORDERS REVIEW. 2018;26(5):462-471
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2018;59(9):966-972
- Article: BIOLOGICAL PSYCHIATRY. 2018;84(5):324-331
- Article: MOLECULAR PSYCHIATRY. 2018;23(7):1659-1665
- Article: MOLECULAR PSYCHIATRY. 2018;23(7):1652-1658
- Article: MOLECULAR PSYCHIATRY. 2018;23(5):1189-1197
- Article: JOURNAL OF THE AMERICAN HEART ASSOCIATION. 2018;7(9):e007806
- Article: MOLECULAR PSYCHIATRY. 2018;23(2):257-262
- Article: BIOLOGICAL PSYCHIATRY. 2018;83(2):173-180
- Article: JAMA PSYCHIATRY. 2018;75(1):47-55
- Article: AGING. 2017;9(12):2629-2646
- Article: PSYCHOLOGICAL MEDICINE. 2017;47(16):2866-2878
- Article: PSYCHONEUROENDOCRINOLOGY. 2017;85:63-68
- Article: INTERNATIONAL JOURNAL OF EATING DISORDERS. 2017;50(9):1095-1103
- Article: ACTA PSYCHIATRICA SCANDINAVICA. 2017;136(2):156-165
- Article: ANNALS OF THE AMERICAN THORACIC SOCIETY. 2017;14(7):1147-1153
- Article: EUROPEAN CHILD AND ADOLESCENT PSYCHIATRY. 2017;26(7):857-867
- Article: PROSTATE. 2017;77(8):900-907
- Article: JAMA PSYCHIATRY. 2017;74(6):615-621
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2017;58(6):711-718
- Article: SCHIZOPHRENIA RESEARCH. 2017;181:13-16
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2017;58(3):231-239
- Article: JOURNAL OF WOMEN'S HEALTH. 2017;26(2):152-158
- Article: JOURNAL OF THE AMERICAN ACADEMY OF CHILD AND ADOLESCENT PSYCHIATRY. 2017;56(2):167-174.e1
- Article: TRANSLATIONAL PSYCHIATRY. 2017;7(1):e1014
- Article: PLOS ONE. 2017;12(6):e0179541
- Article: CHILD AND ADOLESCENT PSYCHIATRY AND MENTAL HEALTH. 2017;11:57
- Article: CLINICAL EPIDEMIOLOGY. 2017;9:567-577
- Article: JAMA PSYCHIATRY. 2016;73(12):1268-1275
- Article: JAMA PSYCHIATRY. 2016;73(11):1135-1144
- Article: EPIDEMIOLOGY. 2016;27(6):852-858
- Article: GUT. 2016;65(11):1793-1798
- Article: JOURNAL OF THE AMERICAN ACADEMY OF CHILD AND ADOLESCENT PSYCHIATRY. 2016;55(10):886-895
- Article: PSYCHOLOGICAL MEDICINE. 2016;46(14):2981-2988
- Article: ADDICTION. 2016;111(10):1814-1822
- Article: PSYCHOLOGICAL MEDICINE. 2016;46(12):2637-2646
- Article: MOLECULAR PSYCHIATRY. 2016;21(8):1077-1084
- Article: TRANSLATIONAL PSYCHIATRY. 2016;6(5):e796
- Article: PSYCHOLOGICAL MEDICINE. 2016;46(5):1091-1102
- Article: JAMA PSYCHIATRY. 2016;73(3):284-291
- Article: AMERICAN JOURNAL OF PSYCHIATRY. 2016;173(2):158-165
- Article: AMERICAN JOURNAL OF HUMAN GENETICS. 2015;97(5):708-714
- Article: FERTILITY AND STERILITY. 2015;104(4):947-952
- Article: JAMA PSYCHIATRY. 2015;72(10):971-978
- Article: AMERICAN JOURNAL OF MEDICAL GENETICS, PART B: NEUROPSYCHIATRIC GENETICS. 2015;168(6):414-422
- Article: JOURNAL OF THE AMERICAN ACADEMY OF CHILD AND ADOLESCENT PSYCHIATRY. 2015;54(7):565-570
- Article: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2015;56(6):640-647
- Article: BIPOLAR DISORDERS. 2015;17(2):184-193
- Article: PSYCHOLOGICAL SCIENCE. 2015;26(1):78-88
- Article: INTERNATIONAL JOURNAL OF EPIDEMIOLOGY. 2014;43(6):1815-1824
- Article: BEHAVIOR GENETICS. 2014;44(5):456-467
- Article: PSYCHOLOGICAL SCIENCE. 2014;25(9):1795-1803
- Article: INTERNATIONAL JOURNAL OF EPIDEMIOLOGY. 2014;43(3):835-842
- Article: JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION (JAMA). 2014;311(17):1770-1777
- Article: JAMA PSYCHIATRY. 2014;71(4):432-438
- Article: BRAIN. 2014;137(Pt 3):770-778
- Article: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA. 2014;111(3):1032-1036
- Article: EPIDEMIOLOGY. 2012;23(5):713-720
- Article: DEVELOPMENT AND PSYCHOPATHOLOGY. 2012;24(3):739-753
- Article: PSYCHOLOGICAL MEDICINE. 2012;42(1):111-123
- Article: INTERNATIONAL JOURNAL OF EPIDEMIOLOGY. 2010;39(6):1531-1540
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Alla övriga publikationer
- Letter: JAMA PSYCHIATRY. 2024;81(6):631-632
- Preprint: MEDRXIV. 2024;MEDRXIV
- Preprint: MEDRXIV. 2024;MEDRXIV
- Preprint: RES SQ. 2023;RES SQ
- Preprint: RESEARCH SQUARE. 2023
- Corrigendum: TRANSLATIONAL PSYCHIATRY. 2022;12(1):192
- Preprint: PSYARXIV. 2022
- Preprint: MEDRXIV. 2021
- Preprint: RESEARCH SQUARE. 2021
- Corrigendum: MOLECULAR PSYCHIATRY. 2021;26(7):3210
- Editorial comment: PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. BIOLOGICAL SCIENCES. 2021;288(1947):20210304
- Preprint: MEDRXIV. 2021
- Review: JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY. 2020;61(11):1173-1183
- Preprint: MEDRXIV. 2020
- Letter: THE LANCET PSYCHIATRY. 2018;5(12):963-964
- Review: THE LANCET PSYCHIATRY. 2018;5(9):717-726
- Preprint: BIORXIV. 2018
- Preprint: BIORXIV. 2018
- Letter: JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION (JAMA). 2017;318(12):1182-1184
- Review: BEHAVIOR GENETICS. 2016;46(3):315-328
- Review: AMERICAN JOURNAL OF MEDICAL GENETICS, PART B: NEUROPSYCHIATRIC GENETICS. 2015;168(6):406-413
- Letter: BRAIN. 2014;137(Pt 7):e288
- Thesis / dissertation: 2014
- Visa fler
Forskningsbidrag
- Bank of Sweden Tercentenary Foundation1 January 2022 - 31 December 2023
- Swedish Research Council1 January 2020 - 31 December 2022
- Swedish Research Council1 January 2018 - 31 December 2020
Anställningar
- Statistiker, Medicinsk epidemiologi och biostatistik, Karolinska Institutet, 2014-
Examina och utbildning
- Docent, Epidemiologi, Karolinska Institutet, 2020
- Medicine Doktorsexamen, Institutionen för medicinsk epidemiologi och biostatistik, Karolinska Institutet, 2014
Handledare
- Vide Ohlsson Gotby, Register-based studies of sex steroid hormones and psychiatric disorders.