We are pleased to share an important research milestone for the IFS community.
The Center for Mindfulness and Compassion (CMC) at Cambridge Health Alliance (CHA), a Harvard Medical School affiliate, has published the first randomized controlled trial (RCT) evaluating the Program for Alleviating and Resolving Trauma and Stress (PARTS), a 16-week group-based PTSD treatment program derived from Internal Family Systems.
The study, published in the American Psychological Association’s journal Psychological Trauma: Theory, Research, Practice, and Policy, was led by Principal Investigator Zev Schuman-Olivier, MD, Associate Professor of Psychiatry at Harvard Medical School and Director of CMC, along with a multidisciplinary research team. This study was made possible by funding provided by the Foundation for Self Leadership, our non-profit partner.
In this RCT, 60 patients with PTSD were randomized to either the PARTS intervention or an active control group called Nature-Based Stress Reduction for Trauma Survivors. Both treatment arms demonstrated statistically significant and large reductions in PTSD symptoms, measured by the gold-standard CAPS-5 clinician-administered assessment. However, the PARTS group showed higher attendance and greater patient satisfaction compared to the control group.
This study represents the first RCT of a group-based PTSD treatment program derived from IFS. It addresses an important public health need by exploring a structured, accessible group format for trauma treatment. As the authors note, while clinical research on IFS remains in its early stages, continued investigation is essential to understanding where and how IFS-informed approaches are most effective.
Importantly, this research was conducted independently by the team at CHA’s Center for Mindfulness and Compassion and involved professionals trained through IFS Institute. The design, analysis, and findings represent the scientific perspectives of the authors.
The IFS Institute celebrates this important contribution to the research base and remains committed to supporting continued scientific inquiry into IFS and IFS-derived interventions. Expanding rigorous research is essential to strengthening the model’s clinical foundation, increasing access to care, ensuring client safety, and ensuring that growth is guided by evidence as well as experience.
We extend our appreciation to Dr. Schuman-Olivier and the full CHA research team for this meaningful step forward.