Psychopathology — Categorical Screening and Functional Impact
Psychopathology Instruments
OCI-R, SPQ, PDSS-SR, IPDE-SQ, and additional instruments for categorical screening and functional impact assessment.
1. Personality Disorders — IPDE-SQ
The IPDE-SQ (Loranger et al., 1994) screens all 10 DSM-IV personality disorder categories using 77 true/false items. It is designed as a pre-interview screen, not a diagnostic instrument. Positive screens flag which personality disorder categories require follow-up with the full IPDE semi-structured clinical interview.
The IPDE-SQ is optimized for sensitivity: it errs toward false positives rather than false negatives, ensuring that the full interview captures all likely true cases. A positive screen on the IPDE-SQ does not establish a diagnosis — it identifies candidates for diagnostic interview.
IPDE-SQ product page →2. Schizoid–Avoidant Discrimination
The distinction between schizoid and avoidant presentations is one of the most clinically consequential discriminations in personality disorder work. Both present with social withdrawal; the mechanism differs. The avoidant person wants connection but fears rejection (high anxiety, approach-avoidance conflict). The schizoid person does not experience the motivational pull toward connection (low N2B, low PANAS-PA).
Instruments: Revised Social Anhedonia Scale (RSAS) discriminates schizoid withdrawal from anxious avoidance. SPQ captures schizotypal features that may accompany schizoid presentations. N2B indexes motivational baseline.
3. Obsessive-Compulsive Spectrum — OCI-R
The OCI-R (Foa et al., 2002) is an 18-item self-report measure of OCD symptom severity with six subscales: Washing, Obsessing, Hoarding, Ordering, Checking, Neutralizing. A total score ≥21 has acceptable sensitivity and specificity against structured diagnostic interview. The subscale profile maps onto the symptom heterogeneity of OCD.
4. Schizotypal Features — SPQ
The SPQ (Raine, 1991) is a 74-item true/false measure of schizotypal features organized into three factors: cognitive-perceptual (magical thinking, unusual perceptual experiences, ideas of reference), interpersonal (constricted affect, no close friends, excessive social anxiety), and disorganized (odd speech, odd behavior, circumstantial thinking). The SPQ screens for schizotypy as a dimensional trait and for schizotypal personality disorder as a categorical diagnosis.
5. Panic and Dissociation
Panic Disorder Severity Scale — Self-Report (PDSS-SR) is a validated self-report version of the clinician-administered PDSS. Seven items cover panic attack frequency, distress, anticipatory anxiety, agoraphobic fear, situational avoidance, and impairment. The Dissociative Experiences Scale (DES) screens for dissociative phenomena across a 0–100 visual analog format.
6. Substance Use
AUDIT (Alcohol Use Disorders Identification Test) and DAST (Drug Abuse Screening Test) provide brief validated screens for alcohol and substance use disorder severity. Both are widely used as intake screeners in clinical and research settings.
7. Neurodevelopmental: ADHD
Adult ADHD Self-Report Scale (ASRS) and the Wender Utah Rating Scale (WURS) screen for current ADHD symptoms and retrospective childhood ADHD presentation, respectively. The ASRS part A (6 items) has sensitivity .68 and specificity .99 for a current ADHD diagnosis. The WURS operationalizes the developmental continuity criterion central to adult ADHD diagnosis.
8. Functional Impact: WHODAS 2.0
The WHO Disability Assessment Schedule 2.0 (WHODAS 2.0) is a generic assessment of functioning and disability based on the ICF framework. Six domains: cognition, mobility, self-care, getting along, life activities, participation. The WHODAS is disorder-agnostic and can be used across all psychopathology categories to quantify functional impact independently of symptom category. This cross-categorical metric allows direct comparison of functional impairment across diagnostic groups.