Initiative on Immunization Registries
WORKING GROUP MEMBERS AND CONSULTANTS
National Vaccine Advisory Committee
Amy Fine, Privacy and Confidentiality Chair
Marian Sokol, Ph.D., M.P.H., Resource Chair
Patricia Whitley-Williams, M.D.,
National Medical Association
Dennis Brooks, M.D.
Council of State and Territorial Epidemiologists
Steve Waterman, M.D., M.P.H.
American Medical Informatics Association
Immunization Education Action Committee
Centers for Medicare and Medicaid Services
Department of Defense
American Association of Health Plans
Health Resources and Services Administration
Partnership for Prevention
National Association of County and City Health Officials
City of Houston Health Department
All Kids Count
American Academy of Family Physicians
U.S. Department of Agriculture and National Vaccine Advisory Committee
Pharmaceutical Research and Manufacturers of America
Informed Parents Against VAPP (Vaccine-Associated Paralytic
Inter-American College of Physicians
Center for Health Information Management
Association of State and Territorial Health Officials
National Committee for Quality Assurance
American Academy of Pediatrics
CDC Response to a Report from the National Vaccine Advisory Committee
Immunization registries are confidential, population-based computerized systems that contain information regarding children's vaccinations. Registries provide a critical tool for increasing and sustaining vaccination coverage. A national health objective for 2010 is to increase to 95% the proportion of children aged <6 years who participate in fully operational population-based immunization registries. According to 2000 data, 24% of U.S. children are participating in population-based immunization registries. In 1998, to facilitate community- and state-based immunization registry development in the United States, the National Vaccine Advisory Committee (NVAC) launched the Initiative on Immunization Registries. Through public hearings and parent focus groups, NVAC identified four concerns that needed to be addressed to increase registry participation: a) protecting each person's privacy and the confidentiality of registry information; b) ensuring participation of vaccination providers and recipients; c) overcoming technical and operational challenges; and d) determining resources needed to develop and maintain immunization registries. In January 1999, NVAC approved the report Development of Community- and State-Based Immunization Registries (available at <http://www.cdc.gov/nip/registry/nvac.htm>; accessed July 30, 2001). The following report summarizes NVAC's recommendations and describes CDC's National Immunization Program activities in response to NVAC's recommendations.
Vaccinations are a critical public health tool: They save lives, reduce health-care costs, and improve the quality of life for persons of all ages. After safe and effective vaccines were introduced, the United States and the majority of other developed countries have experienced >95% reductions in cases of childhood vaccine-preventable diseases, compared with prevaccine-era levels (1). Reported cases are at record low levels; however, vaccine-preventable diseases will return if vaccination coverage levels decrease (2).
Reaching and Maintaining Increased Vaccination Coverage Levels
Three successful strategies, implemented nationwide during the 1990s, have boosted vaccination coverage to the highest levels ever (3). These strategies include
Maintaining increased vaccination coverage rates is a continuing challenge. In the United States, an average of 11,000 infants are born daily, and each child needs protection against vaccine-preventable diseases. Multiple factors threaten continuing success, as follows:
Together, these factors cause difficulty for parents and providers in determining a child's immunization status and ensuring that each child gets needed vaccinations. Families, providers, and schools need definitive documentation of childhood vaccinations, and communities and public health programs require accurate coverage estimates. Community- and state-based immunization registries are a critical tool for increasing and sustaining vaccination coverage; therefore, one Healthy People 2010 objective is to increase to 95% the proportion of children aged <6 years who participate in fully operational, population-based immunization registries (17).
What Are Immunization Registries?*
Immunization registries are confidential, population-based, computerized systems for maintaining information regarding children's vaccinations. A population-based registry includes the majority of children in a geographic area, regardless of health-care source. Children's names can be entered into the registry at birth (e.g., through a link with electronic birth records) or at first contact with the health-care system. If a registry includes all children in a geographic area and all providers report vaccination and immunization data, the registry can provide a single data source for all community vaccination partners. Registries enable implementing vaccination strategies, and they decrease resources needed to measure, achieve, and maintain increased levels of vaccination coverage. Immunization registries offer potential benefits to parents, communities, health-care systems, and the public health system (Box 1).
Efforts to Build U.S. Immunization Registries
In 1993, CDC began awarding planning grants to develop immunization registries in every state. These systems were intended to collect immunization histories on all children residing in the states. In 1994, NVAC's Subcommittee on Vaccination Registries recommended expanded funding and new federal policies for a system of immunization registries to support national goals. Since 1994, CDC has allocated $181.3 million for the development and implementation of a nationwide network of community- and state-based immunization registries to its 64 immunization grantees (i.e., 50 states, the District of Columbia, Chicago, Houston, New York City, Philadelphia, San Antonio, American Samoa, Guam, Marshall Islands, Micronesia, Northern Mariana Islands, Palau, Puerto Rico, and the U.S. Virgin Islands) that receive federal vaccination funds under section 317 of the Public Health Service Act. Private foundations have also contributed funds for immunization registry development, including approximately $20 million from the Robert Wood Johnson Foundation.
As of December 2000, a total of 39 (61%) of 64 grantees reported operating population-based immunization registries that targeted their entire catchment areas, and an additional 25 (39%) grantees reported developing population-based immunization registries. In 2000, an estimated 24% of children aged <5 years participated in a population-based immunization registry (CDC, unpublished data, 2001).
NVAC's Initiative on Immunization Registries
In 1998, NVAC launched the Initiative on Immunization Registries to facilitate community- and state-based immunization registry development in the United States. Through public hearings and parent focus groups, NVAC's members and consultants to the Initiative on Immunization Registries identified four challenges that needed to be addressed to increase registry participation and to provide a framework for their recommendations:
In January 1999, NVAC approved the report resulting from the Initiative on Immunization Registries (18). The following sections summarize NVAC's recommendations and CDC's National Immunization Program activities in response to those recommendations.
RECOMMENDATIONS AND CDC ACTIVITIES
Protecting Privacy and Confidentiality
In response to these recommendations, a CDC-led Privacy and Confidentiality Implementation Team with representatives from the National Vaccine Program Office (NVPO), state health departments, and the All Kids Count (AKC) program, developed minimum specifications for protecting the privacy of registry participants and the confidentiality of registry data. Their report was reviewed by privacy consultants and other stakeholders and approved by NVAC in February 2000 (19).
The specifications are based on the following principles:
Minimum specifications include, but are not limited to, the following:
Reports from states indicate that confidentiality policies are being developed or modified to be consistent with these specifications. CDC continues to provide technical assistance to states regarding these specifications. Additionally, CDC will assess how well the minimum specifications apply to more substantial, integrated information systems and to data sharing between managed care organizations and registries. CDC and its partners will also explore other privacy concerns, including whether persons reaching age 18 years should be notified that they are in the registry or that their information is being archived.
As registries mature, interstate exchange of immunization information will become more critical. Presently, inconsistent state laws control interstate information sharing. States with stringent legal protections might not allow disclosure to states with less protective laws. Therefore, CDC is facilitating guidelines development for the interstate exchange of information.
Ensuring Participation of Vaccination Providers and Recipients
In 1997, to increase registry participation, CDC funded research projects to a) identify strategies to encourage provider participation; b) improve registry data quality by developing generalizable algorithms that ensure only one record per child in a database; and c) assess the feasibility of avoiding duplicate data entry in provider offices by enabling preexisting billing or patient management systems to report vaccinations directly to an immunization registry.
Among the lessons learned from these projects is that provider participation depends, in part, on high quality registry data. Registries must be able to detect whether incoming information is already in the registry or is new. The majority of registries have developed processes for detecting when a registry contains multiple records for one child. Although no national criteria exist for evaluating the effectiveness of registry duplication-reduction algorithms, efforts are on-going to develop suitable evaluation criteria for these algorithms.
CDC is also developing a computerized tool that can examine registry data accuracy and completeness by comparing registry records with vaccination provider records. Furthermore, CDC is evaluating the feasibility of comparing coverage estimates generated from the National Immunization Survey (NIS), which is a nationwide, random-digit--dial survey of children's vaccination coverage in the United States, with estimates based on registry databases. Concordance rates between registry estimates and established standard estimates should reflect the completeness and accuracy of immunization histories recorded in a registry's database. Increased concordance rates should persuade providers and parents that registry data are of high quality.
CDC has also identified registries that collect timely and complete immunization information for a substantial proportion of their target population or a subgroup of their population. Vaccination coverage estimates from these sentinel sites are reported quarterly to CDC and compared with NIS estimates. These sites have been used to monitor new vaccination recommendation implementation and to demonstrate registry data usefulness in focusing public health interventions.
Even when immunization records are of high quality, making appropriate vaccination decisions is difficult because of the complexity of vaccination schedules. In 1995, CDC released its Programmer's Guide to the Automated Immunization Evaluation Process, which offered assistance in developing automated decision support algorithms that assess a child's immunization history and determine which vaccinations are needed (20). Subsequently, algorithms were created and incorporated into registries. To evaluate those algorithms, test cases were developed, and a public domain algorithm program that can function on multiple computer platforms is available.**
CDC is establishing the Provider Participation Team and Work Group to identify concerns and implement solutions to ensure participation of vaccination providers and recipients in immunization registries. Initially, a national survey of pediatricians will be conducted to understand what they think about immunization registries and what would ensure their participation. Then, state vaccination projects will be surveyed to identify current activities to recruit providers and determine best practices.
Ensuring Registry Functionality
In 1994, before these recommendations were made, CDC distributed the first comprehensive description of the general structure and function of an electronic immunization registry. At approximately the same time, CDC, in consultation with immunization grantees and NVAC, also developed essential data elements to identify a person and describe a vaccination event for record exchange. Core data elements include a) patient name (first, middle, and last); b) patient birth date; c) patient sex; d) patient birth state or country; e) mother's name (first, middle, last, and maiden); f) vaccine type; g) vaccine manufacturer; h) vaccination or immunization date; and i) vaccine lot number.
In 1997, because registries were being developed with different capabilities and designs, CDC, in collaboration with immunization program managers, identified the following 12 essential functions for immunization registries to be fully operational:
In 1999, at the recommendation of NVAC, a technical working group (TWG), which included external registry stakeholders and information technology specialists, was formed. The purpose of the group was to a) reach agreement on standard vocabularies and protocols for data transfer; b) serve as consultants to CDC and recommend registry functional standards; c) assist in determining a registry accreditation or certification method and provide ongoing quality assurance monitoring; and d) indicate ways to facilitate the integration of registry functions into existing information systems. Initial TWG accomplishments were their review and agreement with the proposed functional standards, their development of detailed definitions for these standards, and their identification of a method to certify registries on the basis of these standards.
Progress has also been made in enabling registries to exchange data by using standard coding and transmission rules defined by the HL7 standard (21,22). In 1995, CDC began developing the standard HL7 immunization messages and an implementation guide for immunization record transactions. These messages became a part of the final, balloted HL7 standard in 1997. In 2000, CDC received funding from NVPO to develop a computer application that performs HL7 message functions. Plans include placing this application in the public domain so that each registry developer does not have to develop an application independently.
The technical focus of CDC's registry activities is related to identifying methods to ensure reaching the 2010 health objective. CDC is reviewing measurable criteria that have been proposed for each of the 12 functional standards. Standardized site visit protocols addressing these elements were developed to monitor registry progress in achieving the 2010 health objective relating to registries.
Ensuring Sustainable Registry Funding
Limited information is available regarding immunization registry costs. An AKC study of 16 immunization registry projects in 1997 estimated that the cost of maintaining immunization registries was approximately $3.91/child/year, or approximately $94 million/year nationally to enroll all children aged <6 years and keep them in the registry to age 6 years (23). Similarly, a 1998 CDC study of three registries estimated an average annual cost of $3.38--$6.15/child/year, or national costs of $81.1--$147.6 million/year. Additional 1999 CDC-collected data from 24 registries estimated an annual cost of $5.18/child, and an annual national cost of $124.3 million. This study also determined that only 40% of registry costs were funded by federal sources.
Registries offer potential cost savings. Estimated annual fiscal savings of >$270 million associated with registries include costs of manually pulling medical records in provider offices for school or day care entry ($58.0 million); costs of manually pulling medical records in provider offices for changes in primary providers ($16.2 million); costs of duplicative vaccination ($26.5 million); costs of pulling records to fulfill managed care reporting requirements ($2 million); and school system review of immunization records ($168.0 million) (24--26). Registries might also reduce or offset costs by reducing vaccine-preventable disease morbidity and mortality through improved coverage, providing a means for assessing coverage at the local level, and decreasing the incidence of vaccine adverse events through the identification of children who have vaccine contraindications.
Involvement of all stakeholders in considering funding sources for registries will be critical (Box 2). In 2000, the Centers for Medicare and Medicaid Services (formerly the Health Care Financing Administration) agreed to fund approximately 90% of registry development costs for Medicaid recipients. Although certain states have taken this funding opportunity, other sources need to be identified for a long-term funding solution.
OTHER REGISTRY-RELATED CONCERNS
Despite potential benefits of registries to vaccination coverage, program operations, cost-savings, and parental support, immunization registries have critics and opponents. In 1994, a congressional initiative to establish population-based immunization registries throughout the country was proposed. Opponents successfully argued against establishing a national immunization information database. Consequently, efforts to establish state- and community-based immunization registries were begun and have since resulted in the development of state and local registries with different capabilities, legal authority, and success.
Concerns regarding immunization registries and their recommended uses remain, including
Population-based immunization registries, which collect information regarding children within a specified geographic area, can be an effective means for ensuring that children remain current with recommended vaccination schedules. Additionally, registries allow programs to rapidly and completely assess vaccination coverage in defined areas or among specific groups of children. Despite their advantages, registries have developed slowly, and only a limited number of registries are close to meeting the Healthy People 2010 national objective of increasing to 95% the proportion of children aged <6 years who participate in fully operational population-based immunization registries.
In 1998, NVAC held public hearings that produced four recommendations for immunization registries: a) ensure each person's privacy and the confidentially of the information collected; b) ensure participation by all vaccination providers and recipients; c) ensure functionality; and d) ensure sustainable funding. CDC has worked on each of these recommendations with its partners. Minimum specifications to protect privacy and confidentiality have been developed and approved by NVAC. A set of 12 minimum operational standards have been established for population-based immunization registries, and standardized evaluation criteria to monitor registry progress are being developed. The Centers for Medicare and Medicaid Services plans to share the financial burden of state registries. Although these actions do not guarantee that state and local vaccination programs can develop and implement fully operational registries, this national approach to standardization and shared allocation of substantial resources will facilitate this process.
Ensuring participation by all providers and recipients has been more difficult and is not yet close to achievement. Survey data in 2000 estimate that, nationwide, only 24% of children aged <6 years are participating in an immunization registry (CDC, unpublished data, 2001). Although certain national organizations have formally supported the concept of immunization registries, practitioners still find routine participation difficult to implement. Overcoming barriers to full participation remains the greatest challenge to population-based immunization registries.
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*In addition to tracking the vaccinations children receive, fully operational immunization registries can improve vaccine delivery by a) avoiding duplicate vaccinations, b) limiting the cost of missed appointments through the use of reminder or recall notices, c) reducing vaccine waste, and d) reducing staff time required to find or produce immunization records or certificates. In certain regions, immunization registries provide programs a rapid and reliable mechanism for evaluating their vaccination coverage and patterns of use for specific vaccines. Also, registries can assist in vaccine safety efforts and can be used for vaccine ordering and inventory control. Therefore, the term immunization registry is used throughout this report, rather than vaccination registry, to better reflect their capabilities.
**The algorithm program is available upon request by calling (404) 639-8739 or by electronic mail at <CASAINFO@cdc.gov>.
***Health Level Seven (Ann Arbor, Michigan) is an American National Standards Institute-accredited organization that develops specifications or protocols for health-care data management. Additional information is available at <http://www.hl7.org> (accessed July 30, 2001).
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