Lessons Learned from Implementing a Centrally Organized, Cross-Sectoral, Patient-Centered Treatment Coordination...

Although effective treatments for substance use disorders (SUDs) are available in Germany, only a fraction of individuals use them. Barriers include the complexity of the addiction support system, implementation challenges, limited coordination and communication between the different sectors and services, and stigma-related factors such as shame and guilt. Innovative, accessible, and patient-centered care models are rarely effectively implemented. The ASSIST study aimed to evaluate the effectiveness of a sector-independent, individualized treatment coordination model compared to standard care. The new intervention was based on a standardized online assessment, a regional competence center, and an individual treatment assistant. Participants were assigned to levels of care and treatment options tailored to their individual goals and substance use profiles.

A randomized controlled trial with a waiting control group (WCG) was conducted in participants with SUDs or at risk for SUDs. The intervention group (ASSIST) received access to the ASSIST intervention; the WCG received treatment as usual. Assessments were performed at four time points (t0 to t3) over a 6-month period. The primary outcome was change in patient satisfaction (ZUF-8) over 6 months, and the secondary outcomes included change in empowerment, change in quality of life, treatment allocation and retention. Outcomes were analyzed using mixed-effects models (primary: over 6 months [t0 to t3]; secondary: over 2 months [t0 to t1]). Fidelity was assessed descriptively.

Between November 2021 and November 2022, 304 participants (mean age 41 years; 78% male) were enrolled and randomized (ASSIST n = 149, WCG n = 155). No significant time*group interaction effects were found for the primary outcome ZUF-8 (b = 0.16; p = 0.503) or for secondary outcomes. However, ASSIST participants were significantly more likely to start accessing services from the addiction support system compared to the WCG. Fidelity analysis showed low adherence among staff of support services, indicating substantial deviations from the intended implementation.

Study success was severely impeded by challenging pandemic conditions and limited support from local stakeholders. The corresponding recruitment barriers restrict the generalizability of our findings, as mainly participants already engaged in specialized treatment settings were included in the study. Nonetheless, the project provides valuable insights for future health interventions in addiction care, highlighting the critical importance of stakeholder commitment, flexibility in implementation, and contingency planning to manage external disruptions.