RESUMO
BACKGROUND: Childhood immunization rates are suboptimal, especially in high-risk populations. Rural residents could constitute a population at high risk for childhood underimmunization; little is known about demographic factors associated with childhood underimmunization. This study compared the immunization rates of urban and rural 2-year-olds and examined the association between demographic factors and underimmunization for rural 2-year-olds. METHODS: We analyzed two nationally representative surveys: the 1991 National Maternal and Infant Health Survey (NMIHS) and the 1993 National Health Interview Survey (NHIS). The study population consisted of children in non-metropolitan statistical areas who were 24 to 36 months of age in the NMIHS and 19 months to 5 years of age in the NHIS. The NMIHS sample contained 4425 children (966 in rural areas) and the NHIS sample contained 2505 children (566 in rural areas). RESULTS: There were no significant differences in immunization rates between rural and urban children. In urban areas, immunization rates were 63.3% (NMIHS) and 65.5% (NHIS) compared with 63.0% (NMIHS) and 67.8% (NHIS) in rural areas. Low income, low family education, nonwhite race, unemployment, and being a female child were associated with underimmunization in one or both data sets. These relationships were not modified by residence in a universal purchase state, where the state purchases and distributes vaccine for all children to reduce the cost and thereby improve access to immunization services. CONCLUSIONS: Approximately one third of children in urban and rural areas were underimmunized. The demographic characteristics of underimmunized children were similar in urban and rural areas; however, the special characteristics of rural areas may require that interventions be tailored to rural needs.