The Individual Music-Centered Assessment Profile for Neurodevelopmental Disorders (IMCAP-ND) is an evaluation instrument made up of three criterion-referenced rating scales designed to examine how clients perceive, interpret, and make music with the therapist while participating in individual improvisational music therapy. The purposes of this study are to determine the inter-rater reliability of the IMCAP-ND’s Scale I: Musical Emotional Assessment Rating Scale (MEARS), Scale II: Musical Cognitive Perception Scale (MCPS), and Scale III: Musical Responsive Scale (MRS); and to examine the inter-rater reliabilities of the MEARS, MCPS, and MRS subscales scores.

Two raters scored 30 music therapy video-recorded sessions (n = 30) featuring individuals diagnosed with autism spectrum disorder using the MEARS, MCPS, and MRS. Findings pertaining to the MEARS are that nearly all of the weighted kappas (98%) can be characterized as “almost perfect,” using Landis and Koch’s interpretive standard for assessing inter-rater reliability. In addition, all of the weighted kappas (100%) for the subscales of the MCPS as well as the subscales of the MRS can be characterized as “almost perfect,” i.e. the highest level of inter-rater reliability.

The statistical evidence from this study strongly supports the inter-rater reliability of the IMCAP-ND’s MEARS, MCPS, and MRS.