Validity and reliability of the Structured Clinical Interview for Depersonalization-Derealization Spectrum (SCI-DER)

Area of Science:

• Psychiatry
• Clinical Psychology
• Psychopathology

Background:

• Depersonalization symptoms are often underdiagnosed, especially sub-threshold presentations.
• Existing diagnostic tools may not fully capture the spectrum of depersonalization experiences.
• A validated instrument is needed to assess depersonalization across a spectrum model.

Purpose of the Study:

• To evaluate the validity and reliability of the Structured Clinical Interview for the Depersonalization-Derealization Spectrum (SCI-DER).
• To assess the instrument's ability to differentiate between patient groups and controls.
• To confirm the hypothesized spectrum-based structure of the SCI-DER.

Main Methods:

• The SCI-DER was administered to 258 patients with mood and anxiety disorders and 42 controls.
• Concurrent validity was assessed using the Dissociative Experiences Scale.
• Reliability and discriminant validity were analyzed statistically.

Main Results:

• The SCI-DER demonstrated excellent reliability and good concurrent validity.
• The instrument successfully discriminated between patients with mood/anxiety disorders and controls.
• Subjects with depersonalization disorder were significantly differentiated from controls using the SCI-DER.

Conclusions:

• The SCI-DER is a reliable and valid instrument for assessing depersonalization and related symptoms.
• The SCI-DER effectively captures a spectrum of depersonalization experiences, including sub-threshold manifestations.
• The instrument supports a spectrum model of depersonalization-derealization disorders.