Measures
Diagnostic assessment. Diagnoses were determined using theDiagnostic Interview for Anxiety, Mood, and Obsessive-Compulsive and Related Disorders (DIAMOND) (Tolin et al., 2018), a structured diagnostic interview based on the DSM-5 (American Psychiatric Association, 2013) that has demonstrated good reliability and validity estimates for anxiety disorders and HD (e.g., adequate inter-rater reliability for anxiety disorders [κ = 0.73] and HD [κ = 0.86]) (Tolin et al., 2018). Interviewers completed a comprehensive training program in administration and scoring of the DIAMOND (www.diamondinterview.org), and were trained to criterion (κ = 0.80 against an expert rater) prior to administering the interview. Interviewers were licensed psychologists or Bachelor’s-level clinical research assistants supervised by licensed psychologists. After administering the DIAMOND, the clinician rated overall global illness severity using the CGI, a 7-point clinician-administered rating of overall symptom severity (1 =Normal ; 7 = Extreme ).
Self-report measures. Self-reported HD severity was assessed using the 23-item Saving-Inventory-Revised (SI-R) (Frost, Steketee, & Grisham, 2004), which has demonstrated adequate reliability as well as strong convergent and discriminant validity. Items are scored on a 5-point Likert scale (0 = None ; 4 =Almost All/Complete ), with higher scores indicating more severe hoarding symptoms. The SI-R yields a total score as well as three subscales (clutter, difficulty discarding, and acquiring).