Dimensions of variation on the CORE-OM

Area of Science:

• Psychometrics
• Clinical Psychology
• Mental Health Assessment

Background:

• The Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) is a 28-item self-report measure assessing well-being, psychological problems, and functioning.
• It includes a risk domain and has been analyzed for alternative structures, including risk and item wording factors.

Purpose of the Study:

• To compare models for the interpersonal factor structure of the CORE-OM.
• To analyze data from 2,140 patients undergoing psychological therapy in the UK.

Main Methods:

• Utilized a multi-method, multi-trait, nested factors solution to analyze CORE-OM item covariance.
• Examined a first-order general factor (psychological distress) and residualized factors for well-being, problems, functioning, and risk.

Main Results:

• The optimal model identified psychological distress as a general factor, with distinct factors for risk and item wording.
• Scale quality for CORE-OM is satisfactory when scored as two scales: non-risk items and risk items.
• The distinction between psychological problems and functioning is obscured by their shared variance with the psychological distress factor.

Conclusions:

• The CORE-OM exhibits a complex factor structure, suggesting scoring as two scales for risk and psychological distress is optimal.
• Differentiating psychological problems and functioning within the CORE-OM is problematic due to high common variance with psychological distress.
• An alternative strategy for operationalizing the distinction between problems and functioning is proposed.