need training and information resources to track changes in vaccines and vaccination schedules and to maintain office practices that support those schedules.
Some concerns regarding immunization practices are common to many providers, but the responses to them may vary. The resources in public health clinics or community and migrant health centers may differ from those in HMOs or private practices. Providers in urban and rural areas may find different opportunities and constraints. Differences in the mix of providers in communities and states will also affect how immunization practices are addressed. In states where public health clinics are common, those clinics are primary care providers for some children and a source of free or lower-cost immunizations for other children who receive most of their care from private providers. Massachusetts, however, does not have the public health clinics that exist elsewhere. It relies largely on private providers and some community health centers; of 2,500 health care provider sites, 1,000 are individual practices. Federally funded community and migrant health centers provide primary care to a highly mobile population in underserved rural and urban communities where children are at high risk for delayed immunization.
The complex mix of public and private providers and the diversity of settings in which immunization services are delivered argue for emphasizing provider-based changes and for offering providers resources that facilitate change. Regulatory steps can be taken but are neither desirable nor sufficient in many cases. Providers need to recognize that immunization rates for preschool children are too low and that changes in their immunization practices can improve those rates. Peter Szilagyi, from the University of Rochester School of Medicine and Dentistry, told the workshop that a national survey of pediatricians and family physicians (Szilagyi et al., in press) suggested that pediatricians, younger physicians, and providers in urban areas tended to have more aggressive immunization practices. He cautioned, however, that survey responses may overstate actual practice.
In fact, many providers overestimate their success in immunizing children and need better information about their actual performance. For example, Susan Lett reported that providers in Massachusetts estimated that 86–100 percent of children in their practices were fully immunized, but measured coverage was only 37–83 percent. Szilagyi noted that the national survey found that nearly 50 percent of the pediatricians and nearly 70 percent of the family physicians had no mechanism to identify children in their practices who were behind on their immunizations.