**5. Conclusions**

Our systematic review identified evidence to support a dramatic rise in suicide mortality among Greenlandic men aged 15–24 from the mid-1970s, who then represented the highest risk group from 1976–2011 compared with men and women of all age groups in Denmark and Greenland. However, as no articles investigated risk factors for suicide in young men we lack clear explanations for these disparities. Our findings identify a gap in the evidence describing how and when age group transitions occurred in Greenland, and whether this was related to the rapid social change in Greenland at that time. Our findings also identified the need for studies identifying specific suicide risk factors in young men to inform future suicide prevention strategies.

**Author Contributions:** Conceptualization, H.S. and A.P.; methodology, H.S. and A.P.; database search, H.S.; study screening & critical appraisal, H.S., R.F., and A.P.; writing—original draft preparation, H.S. and A.P.; writing—review and editing, H.S., R.F., and A.P.

**Funding:** This research received no external funding. Pitman is part-supported by the UCLH NIHR Biomedical Research Centre (BRC).

**Conflicts of Interest:** The authors declare no conflict of interest.
