Marianne Welmers

Abstract Background Alliance has been shown to predict treatment outcome in family-involved treatment for youth problems in several studies. However, meta-analytic research on alliance in family involved treatment is scarce, and to date nometa-analytic study on the alliance – outcome association in this field has paid attention to moderating variables. Methods We included 28 studies reporting on the alliance - outcome association in 21 independent study samples of families receiving family-involved treatment for youth problems ( N = 2126 families, M age youth ranging from10.6 – 16.1). We performed three multilevel meta-analyses of the associations between three types of alliance processes and treatment outcome, and of several moderator variables. Results The quality of the alliancewas significantly associatedwith treatment outcome ( r = .183, p < .001). Correlationswere significantly stronger when alliance scores of different measurement moments were averaged or added, when families were help-seeking rather than receiving mandated care, and when studies included younger children. The correlation between alliance improvement and treatment outcome just failed to reached significance ( r = .281, p = .067), and no significant correlation was found between split alliances and treatment outcome ( r = .106, p = .343). However, the number of included studies reporting on alliance change scores or split alliances was small. Conclusions Our findings demonstrate that alliance plays a small but significant role in the effectiveness of family-involved treatment. Future research should focus on investigating themore complex systemic aspects of alliance togain fuller understanding of the dynamic role of alliance in working with families.