The full exclusion/inclusion criteria for the study are
presented in Appendix A. The review encompassed
both individual-level and population-level studies.
Given that intimate relationships are a social
phenomenon with potentially different meanings in
different cultural contexts, it was important to
ensure the review was specific to countries with
some broad cultural and economic similarities. The
decision was therefore taken to include only studies
of Organisation for Economic Co-operation and
Development (OECD) countries with a broadly
European cultural heritage.