Larissa van der Giessen
Larissa is a psychologist and PhD researcher working in transitional psychiatry, focusing on youth aged 16–25 years. Her work aims to improve continuity and developmental fit of mental health care during this vulnerable life stage. Her work adopts a transdiagnostic perspective, with attention to themes such as self-harm, self-esteem and childhood maltreatment. Among others, she is involved in the development and evaluation of innovative (waitlist) interventions. A central theme in her work is connection—within the therapeutic relationship, between young people and their social environment, and in relation to nature and animals as potential sources of support and recovery. Her research employs a combination of qualitative and quantitative methods, including the experience sampling method, to capture a comprehensive and nuanced understanding of young people’s experiences and needs during this transitional life stage.
Marijn Andree
Marijn works in transitional psychiatry and is committed to improving continuity of care for adolescents and young adults during vulnerable life stages. As a licensed health care psychologist with over fifteen years of experience in diagnostics, treatment, and multidisciplinary collaboration, she focuses on age-appropriate, integrated care that meets the unique developmental needs of this population. Her expertise includes transitional psychiatry, early detection and intervention, complex developmental and personality disorders, and transdiagnostic treatment approaches. In addition, she is actively involved in care policy and process development, with a strong emphasis on quality, knowledge sharing, and seamless care across age boundaries.
Transitional Psychiatry: Continuity of Care in a Vulnerable Life Stage
This lecture explores the complex developmental and mental-health challenges that arise during the transition from adolescence to early adulthood (16-25 years) — a period marked by rapid change, increasing autonomy, and heightened vulnerability. Despite increasing awareness of youth mental-health needs, the current organization of mental health services often creates gaps precisely when continuity of care is most essential. This presentation offers insight into the needs of transition aged youth as well as barriers young people encounter when navigating mental-health systems. The consequences of fragmented care are examined, with a clear focus on the importance of timely, well-coordinated interventions. Drawing from real-world examples, the lecture highlights initiatives in early intervention and shows how these approaches can be tailored to better support young people during their transition to adulthood. The goal is to deepen understanding of the importance of age-appropriate, flexible, and integrated mental-health care — and to encourage reflection on how services can evolve to more effectively meet the needs of this population.