Marianne Welmers

Abstract Background Home-based family treatment (HBFT) is a widely implemented youth care service. Alliance has been shown to predict treatment outcome of HBFT, however, studies so far failed to account for systemic complexity in alliance that is typical of systemic family treatment. Objectives Investigating associations between family members’ unbalanced alliances and the within-family alliance or shared sense of purpose (SSP) , and improvement of youth behavior problems in a Dutch HBFT for youth problems. Methods Participants were 29 families receiving HBFT for youth problems. We performed correlation analyses between observed early- and mid-treatment SSP, differences between family members in observer-, therapist- and self-reported early andmid-treatment alliances, and youth behavior problems 18months post-treatment. Considering the small sample size and resulting limited statistical power, we also reported trend-significant and substantial non-significant correlations that might be of theoretical importance. Results A greater imbalance in observed early-treatment alliances was associated with less externalizing and total youth behavior problems at follow-up. At mid-treatment this association was in the opposite direction, although small and not significant. Higher levels of mid-treatment SSP were moderately but not significantly associated with the decrease of youth internalizing behavior problems 18 months post-treatment. Conclusions Our findings suggest clinical significance of unbalanced alliances and the family’s shared purpose that warrant further exploration. Ongoing research should examine effects of the interaction between multiple family members’ alliances and of the family’s shared purpose, their development over treatment, and their predictors, to allow for further understanding of the complex role of alliance in HBFT.