Background The Communities That Care (CTC) prevention planning and implementation system trains communities throughout a five-phase cycle to (1) build capacity for prevention, (2) adopt science-based prevention, (3) assess the prevention needs of adolescents living in the community, (4) select, and (5) implement evidence-based programs according to their needs. After CTC proved to be effective and cost-effective in the U.S., it is being used by an increasing number of communities in Germany. The aim of this study is to evaluate the effectiveness and cost-effectiveness of CTC in Germany. Methods Communities in CTC-phases 1 to 3 (n = 21) and individually-matched comparison communities (n = 21) were recruited for a non-randomised trial. To assess long-term outcomes, (1) a cohort of 5th Grade students will be surveyed biennially concerning behaviours (antisocial behaviour and substance use) and well-being as well as risk and protective factors. Additionally, (2) biennial cross-sectional surveys will be conducted in 6th, 8th, 10th, and 11th Grade in each community. To assess short-term outcomes, a cohort of ten key informants per community will be surveyed biennially concerning adoption of science-based prevention, collaboration, community support and community norms. (4) In a cross-sectional design, all ongoing prevention programs and activities in the communities will be assessed biennially and data will be collected about costs, implementation and other characteristics of the programs and activities. (5) To monitor the CTC implementation, the members of the local CTC-boards will be surveyed annually (cross-sectional design) about team functioning and coalition capacity. Data analysis will include general and generalised mixed models to assess the average treatment effect of CTC. Mediation analyses will be performed to test the logical model, e.g., adoption of science-based prevention as a mediator for the effectiveness of the CTC approach. Discussion This is the first controlled study to evaluate the effectiveness of a comprehensive community prevention approach in Germany. Evaluating the effectiveness of CTC in Germany is an important prerequisite for further diffusion of the CTC approach. Trial registration This study was registered with German Clinical Trial Register: DRKS00022819 on Aug 18, 2021.

Aim In Germany, the CTC-EFF (Effectiveness of the Community Prevention System Communities That Care) study, a replication study of the US Community Youth Development Study (CYDS), was rolled out in 2021. This article aims to examine the validity of a translated and adapted version of an instrument that measures five constructs of community capacity for prevention. Subject and methods Twenty-two a priori-matched intervention and comparison communities participated in the study. Two to ten community key informants (n = 182) were interviewed for each community. Exploratory (EFA) and confirmatory factor analyses (CFA) were conducted to assess structural validity. Reliability was assessed at the individual level using McDonald’s omega and at the community level using a generalizability coefficient (GC). Inter-rater agreement was measured using an intraclass correlation coefficient (ICC). Concurrent construct validity was assessed using bivariate correlations and mean comparisons. Results CFA showed good model fit (CFI = 0.964) for the hypothesized five constructs model. Reliability analyses showed good internal consistency at the individual level (omega = 0.86–0.87) and insufficient to moderate reliability at the community level (CG = 0.00–0.62). Inter-rater agreement ranged from insufficient to substantial (ICC = 0.02–0.32). Consistent with theory, three constructs correlated positively at the individual and community level (r = 0.24–0.42). There are no associations between these constructs and interviewer ratings about the respondents’ cooperativeness, trustworthiness, and understanding. Conclusion Three of the five constructs were measured with good validity. Two constructs show insufficient reliability. These will be revised until the next CTC-EFF data collection wave. Further validation is indicated. Trial registration This study was registered with the German Clinical Trial Register, no. DRKS00022819, on August 18, 2021.

Zusammenfassung Hintergrund Communities That Care (CTC) ist ein Ansatz zur Übertragung präventionswissenschaftlicher Grundlagen in die kommunale Präventionspraxis. Mittels Schulungen und Tools unterstützt CTC Kommunen beim Aufbau lokaler Netzwerke zur Förderung der psychosozialen Gesundheit von Kindern und Jugendlichen. Bürgerbeteiligung, intersektorale Zusammenarbeit, wissenschaftsbasierte Prävention, Monitoring und Qualitätsentwicklung sind zentrale Elemente von CTC. Ergebnisse aus den USA legen nahe, dass die Wirkung von CTC auf Gesundheitsverhalten durch fünf intermediäre Outcomes vermittelt wird. Der Beitrag stellt erste Ergebnisse der Studie „Effektivität des kommunalen Präventionssystems Communities That Care“ (CTC-EFF) vor, die die Effektivität von CTC für Deutschland untersucht. Daten und Methoden Die CTC-EFF-Studie ist eine quasiexperimentelle Studie. Einbezogen sind 21 Kommunen, die CTC einführen (IK) und 21 a priori gematchte Vergleichskommunen (VK), die diesen hinsichtlich demographischen, wirtschaftlichen und kriminalstatistischen Merkmalen ähneln. 2021 wurden Befragungen mit 192 kommunalen Schlüsselpersonen (u. a. Amts- und Einrichtungsleitungen) durchgeführt. Bivariat wurde untersucht, ob sich die Befragten von IK und VK hinsichtlich acht soziodemographischer Merkmale, ihrer Einschätzungen zu Präventionszusammenarbeit, intersektoraler Kooperation, finanzieller Unterstützung, Rückhalt in der Bevölkerung sowie Übernahme wissenschaftsbasierter Prävention unterscheiden. Ergebnisse Die Befragten aus IK und VK unterscheiden sich in den soziodemographischen Merkmalen mit Ausnahme der Hochschulzugangsberechtigung (IK: 86 % vs. VK: 96 %) nicht signifikant. Auch werden Präventionszusammenarbeit, intersektorale Kooperation, finanzielle Unterstützung und Rückhalt in der Bevölkerung von den Befragten nicht unterschiedlich eingeschätzt. Eine Ausnahme bildet die Übernahme wissenschaftsbasierter Prävention. Schlussfolgerung Das Matching führte weitgehend zu Baseline-Äquivalenz in den untersuchten Merkmalen. Der kleine Vorsprung der IK gegenüber den VK in der Übernahme wissenschaftsbasierter Prävention ist plausibel, da die IK vor der Erhebung bereits erste Schulungen und Implementationsschritte vollzogen hatten.

Background: In community-based prevention, adopting an evidence-based strategy is known to predict prevention success. Evidence-based prevention includes a theoretical framework, empirical assessment of prevention needs, use of tested and effective prevention programs, monitoring of community prevention efforts and outcomes, and integration of practice experiences. Also known is that adopting evidence-based prevention requires community capacity. However, it is unclear which domains of community capacity are most important for the adoption of evidence-based prevention. This study aims to examine the extent to which specific capacity domains explain variation in evidence-based prevention. Methods: The present study is a secondary data analysis based on a survey of 182 key informants in 38 communities. To determine the validity of the measurement, structural validity, internal consistency, and inter-rater agreement were assessed. Associations between adoption of evidence-based prevention and ten domains of community capacity (participation, knowledge & skills, resources, leadership, community power, collaboration consisting of prevention collaboration and sectoral-collaboration, sense of community, critical awareness & problem solving, and community structure) were investigated at the community level using logistic regression models. Results: Regarding the validation analyses, most findings indicate that the ten community capacity domains could be reliably measured using key informant reports. Results of logistic regression models indicate that adopting evidence-based prevention is related to increased sense of community (OR 6.62; 95 % CI 2.39-18.39), prevention collaboration (OR 26.05; 95 % CI 5.98-13.39), sectoral-collaboration (OR 10.49; 95 % CI 4.04-27.25), community power (19.29; 1.74-28.12), and community structure (OR 4.79; 95 % CI 1.85-12.43). Availability of leadership was predictive of higher chances of adopting evidence-based prevention (OR 5.21; 95 % CI 1.93-14.02). Conclusion: Our findings suggest that communities with higher community capacity have increased chances of adopting an evidence-based prevention strategy.