Diagnosing Obsessive-Compulsive Disorder (OCD) involves a comprehensive evaluation typically conducted by a mental health professional. Here are the steps usually involved in the process: Clinical Interview: The professional will conduct a detailed interview with the individual, asking about their symptoms, the impact of these symptoms on their daily life, their medical history, and their family history of mental health disorders. Psychological Evaluation: This involves discussing thoughts, feelings, and behaviour patterns. It may include questionnaires or psychological self-assessments. Diagnostic Criteria: The professional will compare the individual's symptoms with the criteria for OCD in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association. The DSM-5 criteria for OCD include the presence of obsessions, compulsions, or both, and the habits and compulsions must be time-consuming (take more than 1 hour per day) or cause significant distress or problems in daily functioning. Physical Examination: Sometimes, a physical exam or tests are done to rule out other conditions that could be causing the symptoms. Assessing Severity: If diagnosed with OCD, the severity of the condition is usually evaluated. This can help guide the development of a treatment plan.