Immunization information systems (IIS) are confidential, computerized, population-based
systems that collect and consolidate vaccination data from vaccination providers that
can be used in designing and sustaining effective immunization strategies (1,2). To
monitor progress toward achieving IIS program goals, CDC annually surveys immunization
program grantees using the IIS Annual Report (IISAR). Results from the 2012 IISAR,
completed by 54 of 56 grantees, indicate that 86% (19.5 million) of U.S. children
aged <6 years, and 25% (57.8 million) of U.S. adults participated in IIS. Eight of
12 minimum functional standards for IIS published by the National Vaccine Advisory
Committee (NVAC) (3,4) have been met by ≥90% of grantees. During 2011–2012, progress
was also made in meeting three additional functional standards, including the presence
of core data element fields, timeliness of vaccine records, and Health Level 7 (HL7)
messaging, and will be monitored in new functional standards for IIS published in
2013 (5). Several new and ongoing initiatives, including interoperability between
IIS and electronic health records (i.e., ensuring systems can work together and exchange
information), the use of IIS to support vaccine ordering and inventory management,
the use of two-dimensional barcodes to record vaccination information (1), and collaboration
with pharmacies, federal agencies, and other adult vaccination providers, will support
further progress in meeting functional standards and enhance reporting of adult vaccinations
to IIS.
Of the 56 immunization program grantees (50 states, five cities,* and the District
of Columbia [DC]), 2012 IISAR data† were available for 54 grantees. DC did not report
and New Hampshire was not eligible because it did not have an IIS in 2012. The self-administered
survey asked about participation in IIS, data quality indicators, and IIS functionality
(e.g., interoperability with electronic health records).
Child and Adult Participation in IIS
Child participation was defined as having two or more vaccinations for children aged
<6 years documented in an IIS. Adult participation was defined as having one or more
vaccinations administered to adults aged ≥19 years documented in an IIS. Participation
was calculated by dividing the number of children or adults in an IIS who met their
age group and vaccination criteria by the 2012 U.S. Census estimate of the same age
group in the grantee’s geographic area (6). National estimates were calculated by
summing the number of children or adults reported to be participating and dividing
by the U.S. Census estimate for the total population for that age group.
Nationally, 19.5 million U.S. children aged <6 years (86.2%) participated in an IIS
in 2012. This child participation measure is used to track a Healthy People 2020 objective
(IID-18) to increase to 95% the proportion of children aged <6 years whose immunization
records are in fully operational, population-based IIS (7). Child participation in
IIS has increased steadily, from 63% in 2006 to 86% in 2012 (1). Of the 54 grantees
with available data in 2012, 26 (48%) reported that ≥95% of children aged <6 years
in their geographic area participated in their IIS (Figure 1). Nationally, 57.8 million
U.S. adults aged ≥19 years (24.5%) participated in an IIS in 2012 (Figure 2). Two
IIS did not collect immunization information for adults. The Connecticut IIS includes
only children aged <6 years, and the Rhode Island IIS includes only persons aged <19
years. Adult participation in IIS among the remaining 52 grantees responding in 2012
ranged from 0.5% (Houston) to 85.4% (Minnesota).
Functional Standards for IIS
Functional standards for IIS were developed in 2001 and revised in 2007. The standards
have been approved by NVAC (3,4) for assessing IIS progress in meeting minimum functionalities.
Substantial progress has been made in meeting these functional standards since inception,
and in 2012, eight of 12 functional standards had been met by ≥90% of grantees (Figure
3). Increases were observed during 2011–2012 in the percentage of grantees meeting
three of the four remaining functional standards. The percentage of grantees meeting
functional standard (FS) 1 (i.e., reporting the presence of fields in their IIS for
18 required NVAC core data elements) increased from 57% in 2011 to 65% in 2012. Completeness
of core data elements has been reported on previously (1). The percentage of grantees
meeting FS 4 (i.e., percentage of grantees who reported receiving and processing ≥70%
of vaccine and other immunization encounter information within 30 days of vaccine
administration) increased from 63% in 2011 to 76% in 2012. The percentage of grantees
meeting FS 7 (i.e., meeting basic HL 7 functionality§) increased from 58% in 2011
to 77% in 2012. The percentage of grantees meeting more advanced HL7 functionality¶
increased from 35% in 2011 to 37% in 2012. In 2012, 37% (19) of grantees were sending
and receiving any HL7 v.2.5.1 messages, an increase from 17.3% (9) of grantees in
2011. The percentage of grantees meeting FS 2 (i.e., reporting the establishment of
a birth record within an average time of ≤6 weeks) decreased from 85% in 2011 to 84%
in 2012. This slight decline occurred because three grantees who previously met the
functional standard in 2011 reported a decrease in timeliness in 2012 resulting from
their acceptance of larger amounts of data, which slowed processing times; however,
two grantees achieved the functional standard in 2012 who had not previously.
Editorial Note
Child participation in IIS increased steadily from 2006 to 2012, reaching 86%; adult
participation, however, only reached 25% in 2012. Eight of 12 IIS functional standards
were met by ≥90% of grantees in 2012. Increases in grantees meeting minimum functional
standards for IIS data quality and interoperability, including the presence of core
data element fields, timeliness for vaccination records, and HL7 messaging functionality,
also have been demonstrated from 2011 to 2012, although challenges remain for IIS
to reach their full potential in these areas, and for improving the timeliness of
birth records in IIS.
Historically, the primary focus of IIS and immunization programs has been pediatric
populations. This focus was warranted because of the increasing complexity of the
routine pediatric immunization schedule, mobility of children among different providers
resulting in vaccination record scattering (8) that makes tracking and catch-up immunization
challenging, and the role of the IIS in supporting the Vaccines for Children program
through ordering and inventory management, report generation, and vaccine accountability.
Nevertheless, interest is growing in ensuring that adult populations are included
and vaccinations tracked in IIS. Adults are vaccinated by multiple and diverse providers,
beyond traditional health-care providers (e.g., pharmacies, retail clinics, and subspecialists),
and consolidated adult vaccination records maintained by IIS could play an instrumental
role in providing clinical point-of-care support and population-level immunization
coverage, particularly in special circumstances such as tracking doses administered
during an influenza pandemic.
Currently, 53 of 56 immunization program grantees have IIS with lifespan systems,
yet adult participation in IIS remains low. Challenges to increase adult participation
in IIS include 1) identifying and enrolling the diverse providers that serve adults,
2) a lack of adult immunization reporting mandates in many grantees’ jurisdictions,
and 3) competing priorities for state and local immunization programs. To support
increased adult provider participation in IIS, CDC is supporting several new initiatives,
including partnering with the Veterans Administration, the Indian Health Service,
and federal occupational health clinics; providing supplemental funding to IIS Sentinel
Sites to support adult provider enrollment and completeness of adult data in IIS as
part of pandemic preparedness; and collaborating with the American Immunization Registry
Association to better understand barriers and opportunities for pharmacy reporting
to IIS. CDC also has initiated the Clinical Decision Support for Immunization (CDSi)
project for the adult vaccine schedule, which will provide a single, authoritative,
software-independent foundation for development and maintenance of evaluation and
forecast systems (9).** By capturing Advisory Committee on Immunization Practices
(ACIP) recommendations for adult vaccination in an unambiguous manner, it will improve
the uniform representation of vaccination decision guidelines, and the ability to
automate vaccine evaluation and forecasting (9). CDSi for the childhood schedule was
completed in October 2012 and has already proven successful in clarifying ACIP recommendations
and designing new and existing computer systems.
What is already known on this topic?
In 2011, 84% of U.S. children aged <6 years (19.2 million) participated in immunization
information systems (IIS).
What is added by this report?
In 2012, 86% of U.S. children aged <6 years participated in IIS. Adult participation
(25%) in IIS lags behind. Eight of 12 minimum functional standards for IIS published
by the National Vaccine Advisory Committee have been met by ≥90% grantees, but gaps
still exist in meeting Health Level 7 (HL7) interoperability and some data quality
standards.
What are the implications for public health practice?
To realize the full benefits of IIS, progress is needed to reach lifespan participation
in IIS, advanced bidirectional HL7 messaging between IIS and electronic health records,
and improved data quality in IIS. Initiatives designed to increase adult participation
in IIS, and promote HL7 messaging and electronic health records use among providers,
are expected to support progress in these areas.
In addition to capturing the complete population of children and adults within each
IIS jurisdiction, IIS must maintain and enhance system functionality to ensure that
data quality is high, protect the confidentiality of data, and serve multiple stakeholders.
Although IIS have made great strides in implementing functional standards, progress
can still be made in areas such as timeliness of record submission, completeness of
core data elements, and HL7 functionality. Several ongoing and new initiatives are
expected to support these functional standards, including the use of IIS to support
vaccine ordering and inventory management, the use of two-dimensional barcodes to
record vaccination information, and interoperability between IIS and electronic health
records (1). Implementation of stage 2 meaningful use criteria for the Medicare and
Medicaid electronic health record incentive program (10), emphasizing use of HL7 version
2.5.1 and promotion of successful, ongoing submission from providers to IIS, is expected
to increase child and adult participation in IIS and improve data quality in IIS,
including completeness and timeliness of records. Stage 2 implementation was scheduled
to launch in October 2013 for hospitals and January 2014 for providers.
The findings in this report are subject to at least two limitations. First, although
CDC provides guidance to grantees to validate IISAR responses, data are self-reported
and self-validated, which might result in overestimation or underestimation of participation
rates. Second, because two of the 56 grantees did not report data during the period
studied, the percentage of grantees meeting each of the functional standards might
be higher or lower than calculated.
New functional standards for IIS for 2013–2017 have been developed by CDC through
a consensus process involving input from IIS managers and technical experts nationwide
(5). Those standards are intended to lay a framework for the development of IIS through
2017, and supersede the minimum functional standards for registries adopted by NVAC
in 2001. These new functional standards encompass areas within the old functional
standards where progress is still being achieved, including timeliness of records
submission, completion of core data elements, and HL7 interoperability standards.
They also include new areas, such as supporting the Vaccines for Children program
and state vaccine purchase programs through vaccine inventory functions and capture
of program eligibility at the dose-level, and enhanced data quality through patient-
and vaccine-level de-duplication. Grantees meeting and exceeding these new functional
standards will lead the way in realizing and demonstrating the full potential of IIS.