Columbia subject headings:
Hospital utilization--Length of stay--United States--Statistics.
Hospitals--Rates--United States--Statistics.
Medicare--Statistics.
Older people--Hospital care--United States--Statistics.
Harvard subject headings:
Hospital utilization--Length of stay--United States--Statistics.
Hospitals--Rates--United States--Statistics.
Medicare--Statistics.
Older people--Hospital care--United States--Statistics.
Princeton subject headings: