DRGs are utilized in compensation for health care services in 468 categories based on a preset fixed price per case or diagnosis. Medicare's total payment to the hospital is limited to the amount pre-determined for that DRG. If the hospital receives a patient who does not meet the criteria for admission to the hospital, but requires the same level of care provided to other patients who were admitted, it must provide that service even if doing so results in a loss. Medicaid pays for most services rendered by hospitals to individuals whose income and resources are too high to qualify for assistance but who cannot pay for such services. To be considered eligible for Medicaid, an individual must have a "categorically needy" status. This means they must meet certain requirements to be granted assistance. For example, they must be aged 65 or over; be disabled; be a prisoner; or be a migrant worker. "Totally disabled" under this rule can only be determined through the application process - as there is no medical determination to make - and therefore all persons classified as totally disabled will be eligible for benefits. Hospitals generally do not like to see more expensive patients leave against medical advice (AMA) because this reduces their revenue, which is calculated using the DRG system. However, since AMEs often require specialized treatment that can't be given inside a hospital, they usually won't be covered by any other insurance company.