High-cost users of medical care.

Based on data from the National Medical Care Utilization and Expenditure Survey, the 10 percent of the noninstitutionalized U.S. population that incurred the highest medical care charges was responsible for 75 percent of all incurred charges. Health status was the strongest predictor of high-cost use, followed by economic factors. Persons 65 years of age or over incurred far higher costs than younger persons and had higher out-of-pocket costs, absolutely and as a percentage of income, although they were more likely to be insured.