factors, 0.01-0.16) and likewise by others,36-38 the hoarding factor scores were standardized, with a mean of 0 and an SD of 1. Subjects were dichotomized on the basis of scores greater than 0 or less than 0 on the hoarding factor. Details of this procedure have been presented elsewhere.37,38 We also assessed the severity of hoarding symptoms with the Saving Inventory–Revised (SIR).39 This measure is a validated tool for examining the magnitude of hoarding symptoms and includes facets of this phenomenon not considered in the Y-BOCS symptom checklist.40 Both of these measures of hoarding have been previously characterized and evaluated in our clinical OCD sample.37,40
