Social security defines disability as having a severe, medically determinable impairment that has lasted or is expected to last at least one year. So, a couple things about that. Number one, it has to be pretty severe. It has to be so severe that it keeps you from being able to do eight hours of work a day, five days a week (i.e. full-time employment). Next is the one year requirement. It has to be expected to last a year or has already lasted at least one year, which means it does not include medical conditions that are expected to improve within 12 months. That excludes a lot of claims.