Cognitive Assessment Instrument of Obsessions and Compulsions (CAIOC-13) : A new 13-item scale for evaluating functional impairment associated with OCD

The Cognitive Assessment Instrument of Obsessions and Compulsions (CAIOC) was designed as a novel instrument for clinicians to assess the main cognitive and executive impairments that are hypothesized to underpin the impact of OCD symptoms on functioning in patients with OCD. Initially, 18 items were selected based upon observation in the laboratory and clinical research setting, then refined to a definitive 13-item scale after excluding items due to statistical criteria. In a study involving two raters, 50 patients diagnosed with OCD were assessed using the self-rated and clinician-rated versions of the new scale. OCD patients' scores fell in the region of moderate severity on both clinician and self-rated versions of the CAIOC-13. Inter-rater reliability and Cronbach's alpha scores were satisfactory. Factor analysis indicated a one factor solution confirming its unidimensionality. Significantly higher scores in the OCD group compared to a depression group (n=31) and a healthy control group (n=55) were revealed. Scores on the clinician and self-rated versions of the 13-item CAIOC appear valid and reliable measures of the severity of functional impairment associated with OCD. Further validation, including research into the relationship of the CAIOC-13 with laboratory measures of cognitive impairment and evaluation of its sensitivity is indicated.