A Psychometric Analysis of the Structured Clinical Interview for the DSM-5 Alternative Model for Personality...

Area of Science:

• Psychiatry
• Psychology
• Clinical Assessment

Background:

• Personality disorders are complex, with the DSM-5 Alternative Model for Personality Disorders (AMPD) offering a dimensional approach.
• The Level of Personality Functioning Scale (LPFS) is a key component of the AMPD, assessing core personality functioning.
• Validating assessment tools like the SCID-5-AMPD-I is crucial for accurate diagnosis and treatment planning in personality disorders.

Purpose of the Study:

• To evaluate the psychometric properties of the SCID-5-AMPD-I in assessing the LPFS.
• To investigate the dimensionality of the LPFS using latent variable models.
• To examine the reliability and construct validity of the LPFS within a nonpsychotic patient sample.

Main Methods:

• A heterogeneous sample of 282 nonpsychotic patients was assessed using the SCID-5-AMPD-I.
• Latent variable modeling was employed to analyze the dimensionality of the LPFS.
• Threshold parameters of the 12 LPFS indicators were examined across the latent scale.

Main Results:

• The LPFS, as measured by the SCID-5-AMPD-I, demonstrated unidimensionality.
• Reliable measurement across a broad spectrum of the latent trait was achieved.
• Threshold parameters generally increased across the LPFS levels, supporting the model's predicted ordering, though distinction between Level 2 and 3 warrants refinement.

Conclusions:

• The SCID-5-AMPD-I is a psychometrically sound instrument for assessing the LPFS as a unidimensional construct.
• The findings support the use of the LPFS in clinical settings for evaluating personality functioning.
• Suggestions for improving the distinction between LPFS severity levels include refining interview guidelines and Level 2 indicators.