The TADS-I is a clinician administered semi-structured interview to assess dissociative symptoms and other trauma-related symptoms. The TADS-I was developed by Suzette Boon as a follow-up to the Interview for Dissociative Disorders and Trauma-Related Symptoms (IDDTS) that she previously developed with Helga Matthess. The main objective of the TADS-I is to assess the severity and quality of dissociative symptoms and other trauma-related symptoms. Taking the interview should primarily lead to a statement about the presence of a dissociative disorder.

In addition to questions about the dissociative symptoms, the TADS-I also includes questions about other trauma-related symptoms, including sleep problems, eating problems, anxiety and mood complaints, symptoms of the (complex) post-traumatic stress disorder (PTSD and CPTSS). In this way, the researcher gets a broader picture of the complaints that someone is suffering from and their treatment can be tailored accordingly. Moreover, the interviewer can get an impression whether trauma-related symptoms occur together with dissociative symptoms.

In a pilot study TADS-I was able to reliably differentiate DD patients from patients without a DD. DD patients differed significantly from non-DD in severity on all symptom profiles, also on the severity of trauma-related symptoms and alterations of consciousness (Boon, Cavaletti and Boldrini, 2025)

In 2022, the book Assessing Trauma-related Dissociation, including the full TADS-I interview has been published in Dutch. The English translation of this book and the TADS-I has been published in 2023 by Norton Publishers. At this moment there is al a Finnish, Italian, German and Ukranian translation of the book available. French and Spanish translations of the book will be published this year.

Although the interview is now available, a training is advised. If you are interested in following a training, you can contact me. Trainings are given regularly both online and in person. Please go to the page planning.

Earlier versions of the TADS-I are translated in Finnish, Norwegian, Swedish, German, French, Italian, Spanish, Polish, Estonian and Rumanian, Hungarian, Danish, Slovak and Russian and Ukrainian.

Boon-Langelaan, S. A., Cavalletti, M., Boldrini, M. P., & Runhaar, M. (2025). The Trauma and Dissociative Symptoms Interview (TADS-I): Results of a pilot study. European Journal of Trauma & Dissociation, 100611.