Structured clinical interview for diagnosing obsessive-compulsive spectrum disorders.

Background: There are several established structured diagnostic interviews that cover common mental disorders seen in general psychiatry clinics. The administration of more focused diagnostic interviews may be useful in specialty clinics, such as OCD clinics. A semi-structured clinician-administered interview for obsessive-compulsive spectrum disorders (SCID-OCSD) was developed and adapted for DSM-5/ICD-11 obsessive-compulsive and related disorders as well as other putative obsessive-compulsive spectrum conditions.

Objective: To introduce a semi-structured diagnostic interview for in-depth assessment of obsessive-compulsive spectrum disorders (OCSDs), and to report on its implementation in adults with primary OCD attending an OCD-specialized unit.

Methods: Patients with primary OCD were interviewed using the SCID-OCSD. The SCID-OCSD assesses disorders drawn from several diagnostic categories that share some core features of obsessive-compulsive phenomenology and that are often comorbid in OCD (e.g., obsessive-compulsive related disorders, impulse-control disorders, and a spectrum of compulsive-impulsive conditions such as tics, eating disorders, non-suicidal self-injury, and behavioral addictions. Participants had to be at least moderately symptomatic on the Yale-Brown Obsessive-Compulsive Severity scale (YBOCS, i.e., a total score ≥ 14) to be included in the current study.

Results: One hundred and one adult patients with current OCD (n = 101, 37 men and 64 women), took part in the study. Forty-two participants (n = 42) had OCD and one or more current or past comorbid OCSDs, with excoriation (skin-picking) disorder (n = 16) and body dysmorphic disorder (n = 14) being the most common. Nine (n = 9) participants reported a history of non-suicidal self-injury, and 6 participants reported a history of comorbid tics.

Conclusions: In OCD clinics, the SCID-OCSD may help diagnose the full range of putative OCSDs, and so facilitate treatment planning and research on these conditions.