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).