The Music Therapy Session Assessment Scale (MT-SAS): Validation of a new tool for music therapy process evaluation

Background: Music therapy (MT) interventions are aimed at creating and developing a relationship between patient and therapist. However, there is a lack of validated observational instruments to consistently evaluate the MT process. Aim: The purpose of this study was the validation of Music Therapy Session Assessment Scale (MT-SAS), designed to assess the relationship between therapist and patient during active MT sessions. Methods: Videotapes of a single 30-min session per patient were considered. A pilot study on the videotapes of 10 patients was carried out to help refine the items, define the scoring system and improve inter-rater reliability among the five raters. Then, a validation study on 100 patients with different clinical conditions was carried out. The Italian MT-SAS was used throughout the process, although we also provide an English translation. Results: The final scale consisted of 7 binary items accounting for eye contact, countenance, and nonverbal and sound–music communication. In the pilot study, raters were found to share an acceptable level of agreement in their assessments. Explorative factorial analysis disclosed a single homogeneous factor including 6 items (thus supporting an ordinal total score), with only the item about eye contact being unrelated to the others. Moreover, the existence of 2 different archetypal profiles of attuned and disattuned behaviours was highlighted through multiple correspondence analysis. Conclusions: As suggested by the consistent results of 2 different analyses, MT-SAS is a reliable tool that globally evaluates sonorous–musical and nonverbal behaviours related to emotional attunement and empathetic relationship between patient and therapist during active MT sessions.