| Study | Exclusion reasons | Rmk | Reference |
|---|---|---|---|
| Kornum, 2010 | repeat population groups, duplicate reports (most recent study included) | EXCLUDED: data of Northern Denmark (approximately 31% of the Danish population) between 1991–2007, mainly included in the entire Danish nationwide cohort study (1997-2009) published by Jimenez-Solem 2012. |