FACE VALIDITY AND INTER-RATER RELIABILITY OF THE ENGAGEMENT SCALE PROVIDED IN THE MUSIC THERAPY SOCIAL SKILLS ASSESSMENT: A FULL CROSSED DESIGN

Engagement in music is the precursor to neurologic change in music therapy through neuroplasticity, which necessarily depends on neuronal stimulation from the environment (Castren, 2005; Taylor, 2010). Music therapists treat people with a variety of diagnoses where absence of engagement in meaningful tasks or socialization is an indicator of negative symptoms in the Diagnostic and Statistical Manual of Mental Disorders, such as Major Depressive Disorder, Schizophrenia, and Autism (American Psychological Association [APA], 2013). The aim of this study was to: 1. Establish face validity of the Engagement Scale of the Music Therapy Social Skills Assessment by finding and integrating commonalities from engagement literature across disciplines; 2. Determine the Inter-Rater Reliability of the Engagement Scale. Two coders were selected from a convenience sample of Board Certified Music Therapists. After exceeding the needed a priori of Krippendorff’s alpha the coders rated 16 videos of individuals of a variety of ages and populations in their engagement with music. Subsequent results yielded a tentative reliability of .6836. Further recoding of the experimental data to fit an integrated and shorter scale of engagement resulted in a higher level of tentative reliability of .7505. KEY WORDS: Engagement, Music therapy, Inter-rater reliability, Face validity.