​Several states are considering adoption of policies to collect health data for Asian Americans that is disaggregated by ethnic subgroup, which may identify disparities in access to care. Authors examined health care coverage and access to care between non-Hispanic white and Asian American adults following the Patient Protection and Affordable Care Act (ACA) in California, comparing outcomes in non-Hispanic white adults with all Asian Americans in our sample, and then evaluating whether disparities were detected when data is disaggregated into five of the most populous ethnic subgroups (Chinese, Korean, Filipino, Vietnamese, and Japanese). California Health Interview Survey (CHIS) data were collected between January 2014 and December 2016 for 19,201 non-Hispanic white and 3,077 Asian American nonelderly adults age 18 to 64 living in California. Measured outcomes were (1) being uninsured, (2) having a usual source of care, (3) delaying necessary medical care, and (4) delaying necessary prescription medications. 

Compared with non-Hispanic whites, some subgroups of Asian Americans reported significantly worse access to care: disaggregated, adjusted analyses revealed that Koreans were significantly less likely to report a usual source of care relative to non-Hispanic whites. Chinese and Vietnamese adults were significantly less likely to delay necessary care. 

Authors conclude that disaggregated analyses identified differences in access to care for Asian American subgroups following the ACA. State policies to collect disaggregated health data for Asian Americans may reveal heterogeneity in experiences of care and inform specific policies to reduce disparities in access to care.