摘要：Objectives. We compared health insurance status transitions of nonimmigrants and immigrants. Methods. We used multivariate survival analysis to examine gaining and losing insurance by citizenship and legal status among adults with the Los Angeles Family and Neighborhood Survey. Results. We found significant differences by citizenship and legal status in health insurance transitions. Undocumented immigrants were less likely to gain and more likely to lose insurance compared with native-born citizens. Legal residents were less likely to gain and were slightly more likely to lose insurance compared with native-born citizens. Naturalized citizens did not differ from native-born citizens. Conclusions. Previous studies have not examined health insurance transitions by citizenship and legal status. Policies to increase coverage should consider the experiences of different immigrant groups. Health insurance coverage is an important predictor of preventive and therapeutic medical care. 1, 2 For example, Sudano and Baker found that individuals who had been uninsured at any time during the previous 2 years were less likely to obtain important preventive services, such as Papanicolaou tests and cholesterol tests, compared with individuals who had remained insured throughout the 2 years. 2 Several studies have also found that uninsured individuals delay obtaining needed medical care, even putting off visits to a doctor when they are sick. 3– 6 Cross-sectional studies have repeatedly shown that immigrants are much less likely to be insured than are native-born Americans. 7– 10 In the 1997 Current Population Survey (CPS), 34% of immigrants were uninsured compared with only 14% of native-born Americans. 10 Studies have also found that insurance coverage for immigrants differs by citizenship status. 7, 10, 11 In the 1997 CPS, 44% of noncitizen immigrants were uninsured compared with 19% of immigrants who were US citizens 10 ; in the California Health Interview Survey (CHIS), 51% of noncitizens without a green card were uninsured compared with 32% of noncitizens with a green card, 17% of naturalized citizens, and 11% of those who were native born. 7 Because most surveys, such as the CPS, do not collect information on legal status, 9, 10, 12 previous studies estimated rather than measured coverage for undocumented immigrants. These estimates suggest that undocumented immigrants have a much higher uninsured rate than do other groups. For example, basing their estimate on 1999 CPS data, Brown et al. 9 estimated that 65% of undocumented immigrants were uninsured in California. Lack of health insurance compromises the ability of immigrants to access care. Insured immigrants had significantly better access to care than did uninsured immigrants in an analysis of the 1997 National Survey of America Families. 12 The 2 main sources of health insurance are employment-based health insurance and public programs. 13 Past research suggests that immigrants have less insurance coverage primarily because their socioeconomic circumstances make them unlikely to be eligible for these types of health insurance. For example, the lower average educational attainment of immigrants makes it likely that they will find lower-status jobs without insurance coverage and jobs in industries that do not typically offer employment-based health insurance. 7, 14, 15 Immigrants are also more likely to be ineligible for certain public insurance programs. The 1996 Personal Responsibility and Work Opportunity Reconciliation Act prohibited federal funding of Medicaid for legal immigrants during their first 5 years in the United States—although some states, including California, have used state funds to fill the gap. 16, 17 Past research on immigration and health insurance coverage has been almost exclusively cross-sectional and was focused on insurance status at a single point in time. These analyses are inherently limited, because they ignore the process of gaining or losing coverage over time. The few studies that have examined insurance transitions do not consider whether immigrant status has an independent effect on such transitions. 18, 19 Whether immigration status affects health insurance transitions above and beyond immigrants’ socioeconomic status has important policy implications. For example, if immigrants are less likely to move from an uninsured to an insured status even when occupation and socioeconomic status are controlled, expanding employment-based coverage will not solve the problem of insurance coverage for immigrants. This article makes 3 key contributions. First, it was the only study to date to compare the dynamics of health insurance coverage of immigrants and nonimmigrants. Second, we examined whether immigrant status itself affects coverage after other factors affecting insurance eligibility were controlled. Third, in contrast to previous studies, we used information on legal status to compare insurance coverage for undocumented immigrants with coverage for legal immigrants, naturalized citizens, and native-born Americans.
