Cultural competence (CC) was introduced to reduce substance use treatment (SUT) disparities among migrants and ethnic minorities. However, outcome reviews report limited evidence for its effectiveness in reducing SUT disparities. This paper applies Bacchi’s “What’s the problem represented to be?” approach and an ecosocial perspective in a narrative review (2007–2017) of CC in SUT. This review qualitatively identifies (1) the origin and (2) nature of CC and derivatives in SUT, (3) the presuppositions, (4) how the concepts are questioned and (5) what is left unquestioned. The literature search yielded 41 studies. (1) CC originated in the USA whereas derived concepts are more common in other continents. (2) Components of CC and derivatives are mostly located at the micro (client–provider) level. (3) The most prevalent presuppositions are situated at the micro service user (language, trauma, shame) and the macro level and to a lesser extent at the provider level (ethical requirements, discomfort) and client–provider interaction (distrust, confidentiality, countertransference, worldviews). (4) The authors of the reviewed papers question whether CC is sufficient, how it relates to generalist treatment approaches and whether CC is sufficiently evidence based. (5) Unquestioned issues concern defining culture, formal treatment access, the ‘prevalence presupposition’ and a lack of macro outcome indicators. © 2019, Springer Nature Limited.

WPR approach Migration Migrants Cultural competence Narrative review ethnic minorities

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