Factor Congruence and Psychometric Properties of the Italian Version of the Dimensional Obsessive-Compulsive Scale (DOCS) Across Non-Clinical and Clinical Samples
The Dimensional Obsessive-Compulsive Scale (DOCS) is a self-report instrument that assesses the severity of the four most empirically supported OC symptom dimensions (Contamination, Responsibility, Unacceptable Thoughts, and Symmetry). The aim of this study was to investigate the psychometric properties of the Italian version of the DOCS and address associations with socio-demographical variables, psychometric properties in a community (i.e., non-student) sample, and congruence of factor solutions across non-clinical and patient samples. Factor structure, internal consistency, construct, and criterion validity were investigated in three samples of participants (315 from the general population, 106 OCD patients and 31 with other anxiety disorders [OADs]). Results supported the four-factor structure of the DOCS both in clinical and non-clinical sample, and adequate levels of factor congruence across the two samples were found. DOCS scores showed good internal consistency, temporal stability and construct validity, and could adequately discriminate between non-clinical participants, OCD and OADs patients. All the other variables kept constant, associations of DOCS total score with educational level, of Contamination with gender, and of Unacceptable Thoughts with age were also found. These findings suggest that the Italian version of the DOCS retains the adequate psychometric properties of the original, and can be confidently used as an assessment tool of OC symptoms in clinical and research settings.
KeywordsObsessive compulsive disorder Dimensional obsessive-compulsive scale Assessment Factor analysis Congruence coefficients Italian
Conflict of Interest
The authors declare that this research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. None of the authors nor their institutions at any time received payment or services from a third party for any aspect of this work. There were no financial relationships with entities that could be perceived to influence, or that give the appearance of potentially influencing, what it has been written in this work. No patents and copyrights, either pending, issued, licensed or receiving royalties relevant to this work, need to be declared. There were no other relationships or activities that readers could perceive to have influenced, or that give the appearance of potentially influencing, what it has been written in this work.
All participants volunteered to take part to the study after being presented with a detailed description of the procedure, signed a written informed consent and were treated in accordance with the Ethical Principles of Psychologists and Code of Conduct (American Psychological Association 2002). All procedures were approved by an institutional review board.
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