Factor structure, reliability, and validity of the Japanese version of the Hoarding Rating Scale-Self-Report (HRS-SR-J)

Background: The Hoarding Rating Scale-Self-Report (HRS-SR) is a five-item scale that assesses the symptoms of hoarding. These symptoms include excessive acquisition, difficulty in discarding, and excessive clutter that causes distress. We conducted three studies to examine the factor structure, reliability, and validity of the Japanese version of the HRS-SR (HRS-SR-J). Methods: Study 1 examined its reliability; 193 college students and 320 adolescents and adults completed the HRS-SR-J and, of the college students, 32 took it again 2 weeks later. Study 2 aimed to confirm that its scores in a sample of 210 adolescents and adults are independent of social desirability. Study 3 aimed to validate the HRS-SR-J in the aspects of convergent and discriminant validity in a sample of 550 adults. Results: The HRS-SR-J showed good internal consistency and 2-week test-retest reliability. Based on the nonsignificant correlations between the HRS-SR-J and social desirability, the HRS-SR-J was not strongly affected by social desirability. In addition, it also had a good convergent validity with the Japanese version of the Saving Inventory-Revised (SI-R-J) and the hoarding subscale of the Obsessive-Compulsive Inventory, while having a significantly weaker correlation with the five subscales of the Obsessive-Compulsive Inventory, except for the hoarding subscale. In addition, the strength of the correlation between the HRS-SR-J and the Japanese version of the Patient Health Questionnaire-9 and that between the HRS-SR-J and the Generalized Anxiety Disorder-7 were significantly weaker than the correlation between the HRS-SR-J and the SI-R-J. These results demonstrate that the HRS-SR-J has good convergent and discriminant validity. Conclusion: The HRS-SR-J is a notable self-report scale for examining the severity of hoarding symptoms.