Obsessive-compulsive disorder (OCD) is a chronic psychiatric illness with a mean lifetime prevalence of 2% to 3% in the general population [1
]. OCD is characterized by intense anxiety caused by unwanted, intrusive, persistent thoughts, images, or impulses (obsessions), leading to repetitive behaviours or mental acts (compulsions) that the patient feels driven to perform to prevent or reduce his or her distress or anxiety [2
]. Several self-reporting questionnaires evaluating the severity of OCD have been developed, such as the Yale Brown Obsessive-Compulsive Scale [3
], the Paudua Inventory [4
], the Maudsley Obsessive-Compulsive Inventory [5
], the Vancouver Obsessional Compulsive Inventory [6
], and the Schedule of Compulsions, Obsessions, and Pathological Impulses [7
]. However, these interview-based measures can be time-consuming and expensive, requiring interviewer training and establishment of interviewer reliability. These constraints may preclude their use in many clinical settings.
For these reasons, a comprehensive yet brief self-report measure of the symptoms of OCD would be advantageous. The Obsessive-Compulsive Inventory was specifically developed to measure the intensity of the various symptoms that characterize OCD, assess their frequency and the distress they caused during the previous month, as well as estimating the overall severity of the disorder [8
]. The original OCI consists of seven subscales, namely Washing (eight items), Checking (nine items), Mental Neutralizing (six items), Obsessing (eight items), Ordering (five items), Hoarding (three items), and Doubting (three items). It is rated on a five-point Likert scale to assess the frequency of symptoms and the associated distress. The original version of the OCI has been demonstrated to have good to excellent internal consistency for the full scale and the subscales (r ranged from 0.59 to 0.96), good test-retest reliability for non-clinical samples (r ranged from 0.68 to 0.90) and clinical samples (r ranged from 0.77 to 0.97), and excellent discriminant validity and satisfactory convergent validity [8
]. However, the utility of this scale in clinical setting was limited by its length.
Recently, a shorter, 18-item version of the Obsessions and Compulsions Inventory Revised (OCI-R) was developed by Foa et al [9
]. This revised version was found to have a stable factor structure, high internal consistency for the full scale (ranged from 0.81 to 0.93) and for the subscales (ranged from 0.65 to 0.90), good to excellent test-retest reliability (coefficient r ranged from 0.57 to 0.91), good discriminant validity and satisfactory convergent validity. It has been shown to discriminate patients with OCD from non-clinical samples as well as from patients with anxiety disorder [9
]. In summary, the OCI and the OCI-R were shown to have good psychometric properties in both clinical and non-clinical samples, and have been validated with different versions [10
]. However, all of these validations were done in western samples only.
The purpose of this study was to validate a Chinese version of the OCI-R in a non-clinical sample and a clinical sample with OCD. The availability of the OCI-R in Chinese would definitely provide researchers with additional information to assess the severity of OCD symptoms in the Chinese context, and to facilitate cross-cultural comparison in the near future.