How racial and ethnic groupings may mask disparities: the importance of separating Pacific Islanders from Asians in prenatal care data.

OBJECTIVE: To understand racial/ethnic differences in prenatal care receipt among Pacific Islanders and Asians, who are often combined into a single A/PI category.
METHODS: Retrospective, population-based data were collected by the Vital Statistics branch of the California Department of Health Services. Approximately 2.6 million records of all live California births with a birth certificate in 2000-2004 were included. Analysis focused on prenatal care receipt and population characteristics associated with lack of adequate prenatal care, especially among Asian and Pacific Islander groups.
RESULTS: Pacific Islanders (n = 11,962) were the most likely, compared to any other racial/ethnic group, to have inadequate prenatal care (OR = 2.9, 95% CIs 2.8-3.1), even when controlling for factors known to affect care receipt, specifically maternal age, educational attainment, parity, insurance, geographical region of residence, and maternal place of birth. In contrast, Asian women (n = 295,741) received care closer to that of the White reference group (OR = 1.5, 95% CIs 1.5-1.5). Among Pacific Islanders, Samoans (OR = 3.0, 95% CIs 2.7-3.4) were at particular risk of inadequate care compared to other PI sub-groups.
CONCLUSION: Pacific Islander women received less adequate prenatal care than women of other racial/ethnic groups. The common practice of combining Asians and Pacific Islanders into a single A/PI category may mask needs in the Pacific Islander community. Therefore, in order to continue to reduce health disparities, it may be necessary to collect separate data on these two distinct populations in order to be able to appropriately direct programs and resources.