Who determines the outcome? A three-level meta-analysis on systemic therapy in children and adolescents

Systemic therapy (ST) is a well-established treatment approach to reduce symptoms, yet its effects across outcome domains, informants, and assessment methods remain underexplored.

We conducted a systematic literature review in multiple databases (PsycINFO, Pubmed, Embase, Cochrane CENTRAL), including RCT-studies comparing ST with a psychosocial control treatment for diagnosed children or adolescents. We conducted a three-level meta-analysis. Risk of bias was assessed using an adaptation for psychotherapy.

Overall, we included 44 studies, 370 effect sizes, and 4617 families. The overall effect size was small but significant (g = .16, CI [.09, .23], p < .0001). Contrary to expectations, informants and assessment methods were no significant moderators. Effects were comparable across outcome domains including family functioning (g = .12), caregivers' psychopathology (g = .12) and patient symptoms (g = .19). Outcomes were mostly based on self-report symptom questionnaires, limiting interpretability.

Findings support that ST improves family functioning and caregivers' psychopathology, underscoring the need for more diverse outcomes.