Learning Objectives for this Presentation:
By the end of the presentation participants will be able to understand differences in immunization coverage between American Indian /Alaska Native (AI/AN) and non-AI/AN populations in Arizona.

Background:
The sentinel site study is funded by a Centers for Disease Control and Prevention (CDC) grant to study immunization coverage using registry data. The Arizona registry (Arizona State Immunization Information System, ASIIS) is population-based. Immunization data are received from providers via web-based direct entry, file transfers from clinical and practice management systems, full-function HL-7 interfaces from the Indian Health Service (IHS) and tribal facilities, and a small percent of paper-based reporting. In the Arizona sentinel site region, 29% of the 1-2 year old population is AI/AN.

Objectives:
We compared immunization coverage rates for AI/AN vs. non-AI/AN children 19-35 months in seven counties comprising the northern half of Arizona, our sentinel site study area.

Methods:
We assessed the completeness of the data in ASIIS by comparing the number of AI/AN and non-AI/AN children aged 19-35 months in ASIIS to census projections. We calculated 4:3:1:3:3 coverage using ASIIS.

Results:
The proportions of AI/AN and non-AI/AN children included in ASIIS for the sentinel counties were similar to census projection estimates. Preliminary results show that 4:3:1:3:3 coverage levels in the seven counties combined were significantly higher for AI/AN children than for the non-AI/AN children, with an overall 4:3:1:3:3 coverage of 55.8 (95% CI 54.3 – 57.3) for AI/AN children compared to 34.9% (95% CI 34.0 – 35.8) for non-AI/AN children in those same counties.

Conclusions:
AI/AN children had significantly higher 4:3:1:3:3 coverage than non-AI/AN in the counties studied. Possible reasons may include active use of the IHS registry system, aggressive outreach provided by IHS and tribal facilities serving AI/AN children, and regular immunization assessments of AI/AN children by IHS and tribal facilities.