COSI Study Webinar

This webinar, which took place on 10 December 2025, focuses on sharing the final research findings of the Circle of Security Intervention (COSI) Study (https://www.annafreud.org/research/current-research-projects/the-cosi-study/). The COSI Study was a four-year NIHR funded randomised controlled trial (RCT) that finished in February 2024, co-led by Dr Camilla Rosan and Professor Peter Fonagy. The study explored the clinical and cost effectiveness of a 10-session, group-based intervention called Circle of Security-Parenting (COS-P) for women in 10 different NHS perinatal mental health services (PMHS) across England. COS-P is an intervention designed to help parents manage their difficult emotions and understand the impact of these on the parent-child relationship. The trial compared COS-P, and COS-P and treatment as usual, to treatment as usual with a sample of 371 participants. The study collected data at four different time points (baseline, 3, 7, 12 months), including on participants mental health, emotion regulation skills, perceived parent-infant bonding, and infant developmental outcomes. It also videoed participants playing with their babies and coded these videos for parental sensitivity and attachment security. A qualitative survey was completed with 165 participants and a further 58 were interviewed to provide an in-depth of their experiences, 13 COS-P interveners also took part in focus groups. The webinar will cover both the qualitative and quantitative findings of the trial and link these to research and clinical implications. This webinar will be of interest to clinicians and practitioners delivering COS-P program to women in the perinatal period, and particularly to those working in UK NHS perinatal mental health services. It may also be of interest to those delivering COS-P in other perinatal settings, such as, family hubs, CAMHS, parent-infant relationship teams, and social care. If you find any of this video or the topics discussed triggering, and if you need any support, please follow this link for a list of organisations that can help: https://www.annafreud.org/resources/children-and-young-peoples-wellbeing/young-people-urgent-help/ or find support through the AFC Crisis messenger: https://www.annafreud.org/on-my-mind/afc-crisis-messenger/.