Background: We have established an epidemiological obsessive-compulsive disorder (OCD) cohort in Sweden. Individuals contributed DNA for genotyping and sequencing and also completed a Swedish translation of the Obsessive-Compulsive Inventory-Revised (OCI-R), a self-report questionnaire for assessing the severity and type of symptoms of OCD. This study made use of the OCI-R data to examine the severity and symptom dimensions of OCD as well as comorbidity with other psychiatric disorders. Methods: OCI-R data for 1,134 individuals were available for this study, 1,010 diagnosed with OCD, and 124 diagnosed with chronic tic disorders without OCD used as a comparison group. We first evaluated the psychometric properties of the Swedish translation of the OCI-R. Then, we linked data from the Swedish national registries to access and analyze psychiatric comorbidities of OCD. Results: The Swedish translation of OCI-R demonstrated internal consistency (Cronbach's α = 0.9) and clear agreement with the OCI-R six-factor model. The mean total OCI-R score for females was significantly higher than for males. The most comorbid psychiatric condition to OCD were anxiety disorders (13.6%) and major depression (12%). We observed that individuals with OCD frequently had additional comorbid psychiatric disorders and that the severity of OCD was significantly higher in individuals with at least one additional psychiatric comorbidity compared to individuals with no psychiatric comorbidity. Conclusion: We showed that the Swedish translation of the OCI-R has appropriate psychometric properties. Using an epidemiological framework, we were able to assess the severity and symptom dimensions of OCD and comorbidity with other psychiatric disorders.

中文翻译：

---

瑞典遗传流行病学强迫症队列中的强迫症症状严重程度和共病精神病诊断

背景：我们在瑞典建立了一个流行病学强迫症 (OCD) 队列。个人贡献了用于基因分型和测序的 DNA，并完成了强迫性清单修订版 (OCI-R) 的瑞典语翻译，这是一种用于评估强迫症症状的严重程度和类型的自我报告问卷。本研究利用 OCI-R 数据来检查 OCD 的严重程度和症状维度以及与其他精神疾病的合并症。方法：本研究可获得 1,134 名个体的 OCI-R 数据，其中 1,010 名被诊断为强迫症，124 名被诊断为无强迫症的慢性抽动障碍作为对照组。我们首先评估了 OCI-R 的瑞典语翻译的心理测量特性。然后，我们将瑞典国家登记处的数据联系起来，以访问和分析强迫症的精神科合并症。结果：OCI-R 的瑞典语翻译表现出内部一致性（Cronbach's α = 0.9）并且与 OCI-R 六因素模型明显一致。女性的平均 OCI-R 总分明显高于男性。与强迫症最共病的精神疾病是焦虑症（13.6%）和重度抑郁症（12%）。我们观察到患有强迫症的个体经常有额外的精神疾病共病，并且与没有精神疾病的个体相比，具有至少一种额外精神疾病的个体的强迫症的严重程度显着更高。结论：我们表明 OCI-R 的瑞典语翻译具有适当的心理测量特性。