The MATRIX, a novel tool exploring dynamic psychotherapy: Preliminary psychometric properties.

Most measures in the field of psychodynamic psychotherapy are bound to a specific theory, and usually focus only on patient processes or therapist interventions. The MATRIX is a newly developed research tool that focuses on events within both the patient and the therapist individually, as well as on dyadic events, and provides the simple and meaningful coding of content for therapy session transcripts in psychotherapy. The present study describes the inter-rater reliability and construct validity of the MATRIX. Reliability of the MATRIX was assessed by applying it to 805 fragments of psychodynamic-oriented psychotherapy sessions. Three independent experts coded fragments, and the tool was examined for reliability. Validity in identifying the theoretical inclinations was assessed by applying the MATRIX to 30 segments (containing 1309 fragments) of sessions that reflect different theoretical orientations. Findings evinced high inter-rater reliability for all dimensions. The MATRIX was found to have high degree of validity for differentiating the theoretical inclinations of segments of sessions. The MATRIX is a reliable and valid measure that may enable moment-to-moment, quantitative, analysis of psychodynamic psychotherapy.