Summary

Pursuant to a congressional request, GAO determined what methods the Centers for Disease Control and Prevention (CDC) uses to identify pockets of underimmunized preschool children and what is known about the effectiveness of methods used.

GAO noted that: (1) CDC officials view identification of pockets of underimmunized children as a state responsibility rather than a federal one; therefore, CDC does not directly implement methods for identifying pockets of underimmunized 2-year-old children; (2) CDC defines pockets of need as specific geographic areas within state or urban jurisdictions that contain large numbers of 2-year-old children who are either underimmunized or at risk of underimmunization; (3) CDC's National Immunization Program instead focuses on increasing the overall immunization rate for the basic series and reducing disease; (4) in fiscal year 1997 guidance for grant recipients, CDC, for the first time, directed states to develop plans for identifying pockets of need; (5) at that time, CDC suggested two identification methods: (a) measuring immunization coverage rates directly; or (b) using surrogate measures that may indicate low coverage rates; (6) GAO found that neither CDC nor the states have assessed how well these or other methods identify pockets of underimmunized children or children at risk for underimmunization, although some appraisals have been published about using these methods to measure or improve coverage rates; (7) nevertheless, almost every state is initiating a new activity, or continuing a previous one, to identify pockets of need; and (8) for example, 20 states are assessing immunization coverage rates of children receiving care in public health clinics as their primary method for identifying pockets; 15 other states are using survey techniques such as door-to-door surveys.