The MBT Adherence and Competence Scale (MBT-ACS): development, structure and reliability.

Area of Science:

• Psychotherapy Research
• Clinical Psychology
• Mental Health Assessment

Background:

• Mentalization-Based Treatment (MBT) is a psychotherapeutic approach.
• Assessing treatment fidelity is crucial for research and clinical practice.
• Existing measures may require validation for specific therapeutic modalities like MBT.

Purpose of the Study:

• To investigate the psychometric properties, specifically reliability, of the Mentalization-Based Treatment Adherence and Competence Scale (MBT-ACS).
• To evaluate the MBT-ACS as a tool for measuring adherence and competence in MBT.
• To determine the scale's suitability for quality control and supervision in psychotherapy.

Main Methods:

• A reliability study involving 18 psychotherapy sessions rated by seven different raters.
• Nine therapists each provided two sessions for the rating process.
• Inter-rater reliability for adherence and competence was calculated using the MBT-ACS.

Main Results:

• High overall inter-rater reliabilities for adherence (.84) and competence (.88) were found with seven raters.
• Reliability remained acceptable even with only two raters (.60 for adherence, .68 for competence).
• Variability in reliability was observed across different items of the scale.

Conclusions:

• The MBT-ACS is a suitable measure for assessing treatment fidelity in Mentalization-Based Treatment.
• The scale is valuable for quality control and clinical supervision in MBT.
• Suggestions for improving reliability include redefining and reducing the number of items on the scale.