Objectives:<br>

Our aim was to summarise the current evidence regarding gender differences in the mental health of unaccompanied refugee minors (URM) and to identify gaps in research.

Setting:<br>

We focused on quantitative studies presenting primary data from Organisation for Economic Co-Operation and Development(OECD)countries. Language was restricted to English or German.

Participants:<br>

To be eligible, a study had to involve (former) URM who immigrated to an OECD country.

Design:<br>

We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The databases MEDLINE, CINAHL, LIVIVO, PSYNDEX and PsycINFO were searched from 1990 to 2017. Studies were judged for eligibility by two independent reviewers each. We narratively summarised our results.

Results:<br>

9 primary studies, all from Europe, examined gender differences in the mental health of URM. The majority of the included studies found female URM to be more often affected by post-traumatic or depressive symptoms than their male counterparts. There is only weak evidence regarding other mental health outcomes. Two studies each conducted gender-specific analyses on anxiety and externalising behaviour, but no statistically significant differences between female and male URM were detected.

Conclusions:<br>

Female gender is associated with a higher vulnerability towards certain mental health problems among URM residing in Europe. However, the lack of representative studies using reliable diagnostic methods indicates that the findings so far should be treated with caution. Further research is needed to clarify the role of gender for mental health in URM and to examine underlying mechanisms.