The PHQ-9 has nine questions based on the criteria listed in the Diagnostic and Statistical Manual of Mental Disorders (DSM) and is easily administered, scored and interpreted. Clients can independently and easily answer the nine questions in the PHQ-9 or the therapist can conduct an interview-type question-and-answer session. Use the PHQ-9 to support an initial diagnosis during the course of treatment, develop treatment plans and monitor the severity of symptoms and progress in treatment.