Those who receive disability benefits are periodically reviewed, to determine if they are still disabled. How often you're reviewed depends on the nature and severity of your condition, and whether it's expected to improve. When improvement is expected, your first review is usually six to 18 months after you became disabled. When improvement is possible but unpredictable, review happens about once every three years. If improvement is not expected, a review is done every five to seven years. When it's time for your next review, you generally receive a letter in the mail. The letter will ask you to answer certain questions about your condition. Sometimes, the agency may decide your case needs no further review at this time. In other situations, they may request a full medical review, at which you must appear. You'll need to take any documents relating to medical treatment or work performed since the last review. A disability examiner and a doctor will carefully study all the facts involved. If you have more than one disabling condition, reviewers will look at the total effect upon your ability to work. Usually, the final decision is based on evidence from your doctors, hospitals or clinics. For more details on disability reviews, contact the social security office.