The Motivational Interviewing Treatment Integrity Code (MITI 4): Rationale, Preliminary Reliability and Validity

Area of Science:

• Psychology
• Behavioral Science
• Clinical Psychology

Background:

• Motivational Interviewing (MI) is an evidence-based approach to behavior change.
• The Motivational Interviewing Treatment Integrity (MITI) code is crucial for assessing MI fidelity.
• Previous versions of the MITI code required updates to reflect new MI evidence.

Purpose of the Study:

• To introduce and evaluate the revised Motivational Interviewing Treatment Integrity code version 4.0 (MITI 4.0).
• To assess the reliability of the MITI 4.0 in evaluating MI treatment integrity.
• To incorporate new evidence-based elements into MI assessment.

Main Methods:

• Four undergraduate raters were trained on the MITI 4.0.
• Raters evaluated 50 audiotapes of MI treatment sessions.
• Inter-rater reliability was assessed using kappa and intraclass correlation coefficients.

Main Results:

• MITI 4.0 demonstrated good to excellent inter-rater reliability for most items.
• Reliability was highest with larger sample sizes and more raters.
• Specific items like Emphasize Autonomy showed lower reliability.

Conclusions:

• The MITI 4.0 is a reliable tool for assessing both technical and relational aspects of MI.
• The revised code enhances the evaluation of MI fidelity.
• Findings have implications for MI research and clinical practice.