This paper presents the development and validation of the Possessions as Others and Self Inventory (POSI). The POSI is a 23-item self-report measure that assesses the extent to which possessions are perceived to be extensions of self and significant others in hoarding disorder. In Study 1 (N = 246 community participants, M age = 33.70), exploratory factor analysis suggested the retention of a six-factor solution consistent with the notion that links between possessions, self, and others have numerous dimensions. Confirmatory factor analysis in Study 2 (N = 307 community participants, M age = 35.13) supported the consistency of the six-factor structure. Convergent validity was buttressed by strong correlations between POSI subscales and hoarding symptomology and beliefs. Following disposal of possessions, a perceived feeling of emptiness within the self appears to be particularly pertinent to hoarding behavior.
