Rural American Indian Medicaid health care services use and health care costs in California.

OBJECTIVES: We determined differences in Medicaid service use and health care costs in a rural Indian Health Service (IHS) user population of American Indians and Alaska Natives as compared with Whites.
METHODS: California Medicaid eligibility and claims files were linked to IHS user files to obtain a sample of Medicaid-eligible American Indian/Alaska Native users (n=7910). A random sample of Whites was matched for age, gender, aid category, length of eligibility, and county of residence (n=15075). We used generalized linear models to compare risk-adjusted use of resources-ambulatory visits, prescriptions, emergency room visits, hospitalizations, and costs-both adjusting and stratifying for dominant source of ambulatory visits.
RESULTS: American Indians/Alaska Natives had significantly lower use of Medicaid-paid ambulatory visits, prescriptions, emergency room visits, and hospitalizations and lower associated costs than Whites. Medicaid-paid total costs and use of services were lower for those who predominantly used Indian health program clinics, as well as for those who predominantly used other sources of ambulatory care.
CONCLUSIONS: Barriers to receiving Medicaid services and payments exist for American Indians/Alaska Natives in the rural IHS-user population. If American Indians/Alaska Natives are to have Medicaid resources comparable to those of Whites, these barriers must be reduced.