The Yale-Brown Obsessive Compulsive scale was developed by Wayne Goodman and his colleagues to rate the severity and types of symptoms that a client my have. It is important to note that the Y-BOCS is not intended to diagnose OCD but is used to rate the severity of symptoms and can be administered throughout therapy to track improvements made by the client. The Y-BOCS is administered as a semi-structured interview where the client responds to questions that are asked by the interviewer. The severity of the obsessive symptoms and compulsive symptoms are rated separately to give the practitioner an idea of what symptoms are most prominent. The semi-structured interview also allows the practitioner to ask the client any additional questions that they may feel will be helpful in treating the client. The Y-BOCS is considered to be a valid and reliable measure with strong internal consistency for the symptom checklist and severity scale. Scoring the test is straight forward and categorises the clients score to having a mild case of OCD to an extreme case of OCD.