Recent trends in Oregon indicated that diabetes is on the rise. Medicaid self-reported data estimated about 11 percent are affected by diabetes, which is twice the prevalence of the general population in Oregon. Little is known about the agreement between self-reported information and medical claims data in the Medicaid population. This study provides an opportunity to compare prevalence of diabetes when the estimates are computed from the two different data sources. A sample of 2,154 Medicaid adults in Oregon (18 to 64 years old) were identified in both the Medicaid claims and self-report survey. The result reported a strong agreement of diabetes definition between the Medicaid claim data and the self-reported survey.