The Nationwide Inpatient Sample is the largest all-payer inpatient care database in the United States, containing data on more than seven million hospital stays from approximately 1,000 hospitals. Its large sample size is ideal for developing national and regional estimates and enables analyses of rare conditions, uncommon treatments, and special populations. The following reports describe the design of the NIS, how the NIS compares to similar databases, and other information on how to use the NIS.

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