Background Conduct disorder (CD) is a complex mental disorder characterized by severe rule-breaking and aggressive behavior. While studies have shown that several therapeutic interventions are effective in treating CD symptoms, researchers call for treatments based on etiological knowledge and potential patho-mechanisms. Mentalization-based treatment (MBT) may represent such a treatment approach: Studies have shown that individuals with CD show mentalizing deficits and that mentalizing might represent a protective factor against the development of the disorder. As MBT focuses on the understanding of social behavior in terms of mental states, fostering mentalizing might help CD individuals to (re)gain an adaptive way of coping with negative emotions especially in social interactions and thus reduce aggressive behavior. For this purpose, MBT was adapted for adolescents with CD (MBT-CD). This is a protocol of a feasibility and pilot study to inform the planning of a prospective RCT. The primary aim is to estimate the feasibility of an RCT based on the acceptability of the intervention and the scientific assessments by CD individuals and their families indicated by quantitative and qualitative data, as well as based on necessary organizational resources to conduct an RCT. The secondary aim is to investigate the course of symptom severity and mentalizing skills. Methods The bi-center study is carried out in two outpatient settings associated with university hospitals (Heidelberg and Mainz) in Germany. Adolescents aged between 11 and 18 years with a CD or oppositional defiant disorder (ODD) diagnosis are included. Participants receive MBT-CD for 6 to 12 months. The primary outcome of the feasibility study (e.g., recruitment and adherence rates) will be descriptively analyzed. Multilevel modeling will be used to investigate secondary outcome data. Discussion Fostering the capacity to mentalize social interactions triggering non-mentalized, aggressive behavior might help CD individuals to behave more adaptively. The feasibility trial is essential for gathering information on how to properly conduct MBT-CD including appropriate scientific assessments in this patient group, in order to subsequently investigate the effectiveness of MBT-CD in an RCT. Trial registration ClinicalTrials.gov, NCT02988453. November 30, 2016 Sources of monetary support Dietmar Hopp Stiftung, Heidehof Stiftung Recruitment status Recruitment complete and intervention complete, follow-up assessments ongoing (Heidelberg). Recruitment and assessments ongoing (Mainz). Primary sponsor, principal investigator, and lead investigator in Heidelberg Svenja Taubner is responsible for the design and conduct of MBT-CD intervention and feasibility and pilot study, preparation of protocol and revisions, and publication of study results. Secondary sponsor and lead investigator in Mainz Esther Sobanski is responsible for the recruitment and data collection in the collaborating center Mainz Recruitment country Germany Health condition studied Conduct disorder, oppositional defiant disorder Intervention Mentalization-based treatment for conduct disorder (MBT-CD): MBT-CD is an adaptation of MBT for Borderline Personality Disorder. This manualized psychodynamic psychotherapy focuses on increasing mentalizing, i.e., the ability to understand behavior in terms of mental states, in patients. MBT-CD includes weekly individual sessions with the patient and monthly family sessions. Key inclusion and exclusion criteria Included are adolescent individuals with a diagnosis of conduct disorder or oppositional defiant disorder aged between 11 and 18 years. Study type Feasibility and pilot study (single-group) Date of first enrollment 19.01.2017 Study status The trial is currently in the follow-up assessment phase in Heidelberg and in the recruitment and treatment phase in Mainz. Primary outcomes Acceptability of MBT-CD intervention (as indicated by recruitment rates, completion rates, drop-out rates, treatment duration, oral evaluation), acceptability of scientific assessments (as indicated by adherence, missing data, oral evaluation), and necessary organizational resources (scientific personnel, recruitment networks, MBT-CD training and supervision) to estimate feasibility of an RCT Secondary outcomes Adolescents’ symptom severity and mentalizing ability Protocol version 20.08.2020, version 1.0

Background Home visitation services within German Early Childhood Interventions (ECI) for families with a child aged 0–3 are mainly provided by frontline pediatric nurses and family midwifes. Home visitors are often challenged by difficult interactions with families. Mentalizing, the ability to understand mental states of oneself and others, is a key skill for building effective working relationships, which in turn positively affect intervention outcomes. The aim of this study was to investigate if a mentalizing skills training offered to home visitors active in German ECI contributes to continued professional development. We investigated, whether the training positively affected the quality of the working relationships with families as well as home visitors’ empathy, self-efficacy, and mentalizing. Methods To test the effects of a single day mentalizing skills training on the working relationship in N = 73 ECI home visitors, we used a quasi-experimental design with repeated measures (T0, T1, T2, T3) across seven weeks in order to assess immediate change from baseline (T0) after the training (T2) and stability of changes at follow up (T3). A literature-based intervention was implemented before the training to estimate possible repeated measurement and expectational effects (T1). Primary outcome was the quality of the working relationship experienced by the home visitors. Secondary outcome criteria were empathy, work-related self-efficacy, self-reported and observer-rated mentalizing. Results Significant positive change in the working relationship quality was observed at T2 and at T3. Results on the secondary outcomes were less consistent, with data indicating improvement in empathy and increase on some but not all components of mentalizing. Conclusions This study provides preliminary evidence that brief mentalizing skills trainings may be an effective method for continuous professional qualification in frontline ECI home visitors who afterwards, experience better working relationships with families. Thus, training participation may positively impact efficacy and implementation of home visitations in ECI.

Conduct disorder (CD) is a common psychiatric disorder in youth characterized by persisting norm-violating or aggressive behavior. Considering high individual and societal burden, feasible and effective psychotherapeutic treatment is desirable. Yet, treatments and research in this patient group are scarce. This study investigates the feasibility of mentalization-based treatment for adolescents with CD (MBT-CD) in terms of acceptability of MBT-CD and scientific assessments by participants as well as necessary organizational resources to conduct a consecutive randomized controlled trial (RCT). Recruitment, adherence and treatment session numbers were descriptively analyzed. Treatment evaluation interviews were qualitatively analyzed. A subset of sessions of therapists without prior MBT experience was rated for MBT adherence. Quantitative data were used to plan a consecutive RCT. Pre to post treatment changes in diagnosis and self-reported aggression, mentalizing and personality functioning were preliminarily analyzed. N = 45 adolescents with CD were recruited. 43% dropped out. Acceptance of scientific assessments was somewhat lower than therapy adherence (questionnaires filled out by ~ 80% of adolescents in treatment), and low at follow-up (25% of treatment completers). Mean session number was 30.3. Most treatment completers were satisfied with MBT-CD. Referrals mainly came from child and youth services and psychiatry. Nine of 16 sessions rated for MBT adherence were adherent. A priori sample size estimation for a prospective RCT with a drop-out rate of 43% yielded a sample of N = 158 to detect an effect f = .15 with 80% power in a repeated measures ANOVA. Pre–post analyses revealed diagnostic improvement in 68%. Of self-reported data, empathy pathology improved. Findings provide a sound basis for a consecutive feasibility and pilot RCT. Trial registration Clinicaltrials.gov, registration number NCT02988453, November 30, 2016, https://clinicaltrials.gov/ct2/show/NCT02988453