“…First author, year n Study design (Country) Comorbidity Data source Schmitt, 2009 (9) 3,769 A regional register study (Germany) Affective; neurotic, stress-related, somatoform; personality and behaviour; schizophrenic disorders GKV database Saxony, interdisciplinary administrative outpatient database from Germany Cheng, 2015 (5) 6,640 A nationwide longitudinal register study (Taiwan) Major depressive disorder, anxiety disorders Taiwan National Health Insurance Research Database Kim, 2015 (12) 1,517 A cross-sectional register study (South Korea) Depression, anxiety, somatization Regional Conscription Register Shin, 2016 (6) 25,419 A nationwide cohort study (South Korea) Psychiatric disorders Korea National Health Insurance Cohort Data Shrestha, 2017 (7) 119,716 A register study from 3 databases (USA) Anxiety, depression, sleep disorders Commercial, Medicare and Medi-Cal databases Egeberg, 2017 (13) 7,937 A nationwide register study (Denmark) Depression, anxiety Danish National Patient Register Thyssen, 2018 (8) 10,038 A register study (Denmark) Depression, anxiety Danish National Patient Register…”