Methods and Data

Definitions and Data Sources.The data for this study come from the March 1999 Current Population Survey (CPS) collected by the Census Bureau. The CPS is used because it is the most recent survey available and is the source of most official government statistics on the uninsured. Moreover, it is one of the best sources of information on persons born outside of the United States—referred to as foreign-born by the Census Bureau⁴. Persons not born in the United States, one of its outlying territories, or to U.S. parents living abroad are foreign-born. All persons born in the United States, including the children of illegal aliens, are natives. For the purposes of this paper, foreign-born and immigrant are used synonymously.

As already described, this paper relies on the definition of insurance used in the government’s publication, Health Insurance Coverage 1998: Current Population Report P60-208. Persons are considered to have health insurance if they respond "yes" to any of a series of questions that asks whether they were covered by insurance in the year prior to the survey provided by an employer, family member’s policy, the government, or by insurance they purchase themselves. Since the survey was conducted in March 1999, it measures insurance coverage for 1998. No adjustments of any kind are made to the definition of insurance or the data in this paper. Totals for the uninsured presented here match those published by the Census Bureau.

This paper examines insurance coverage for persons living in immigrant- and native-headed households. Individuals related to the household head by blood, marriage, or adoption, regardless of their own nativity, are considered to be in an immigrant or native household based on whether the household head is foreign-born or a native. Individuals unrelated to the head are considered immigrant or native based on the nativity of the head of the family in which they reside. For example, a foreign-born husband and wife (one of them would be the head) with two young U.S.-born children are counted as a household of four people living in an immigrant household. If the same family were to rent a room to an unrelated native-born woman with a child of her own, then the woman and her child would be counted as a separate native household, even though she and her child live under the same roof as the immigrant family and are technically in the same household as the immigrant family. Persons who live by themselves or with others to whom they are unrelated are, in effect, their own households and are considered immigrant or native based on their own nativity. Households are defined in this way so that they more accurately reflect the kind of income sharing and insurance eligibility that exists among members of the same family. Its worth noting that individuals unrelated to the household head only comprise about 4 percent of the population, therefore how they are allocated does not substantially affect the results.

Composition of Immigrant Households. Using the above definition, 92.4 percent of the people living in immigrant-headed households were immigrants themselves (67.3 percent) or the native-born child under age 21 (25.1 percent) of an immigrant father or mother based on the March 1999 CPS. In households headed by immigrants who arrived after 1970, 96.3 percent of the people are either immigrants or their U.S.-born children under the age of 21. Therefore, this approach primarily measures insurance coverage for immigrants and their children. Since a child’s standard of living, including access to health insurance, is a function of his parents’ income, this method captures the full effect of immigration on the size of the uninsured population in the United States. Unless otherwise indicated, country of origin and year of entry for immigrant households are based on the responses of the household head.