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Vaccine-Preventable Diseases: Improving Vaccination Coverage in Children, Adolescents, and AdultsA Report on Recommendations from the Task Force on Community Preventive ServicesSummary The delivery and acceptance of recommended vaccinations is an ongoing challenge for health-care providers and health-care and public health systems, but specific interventions can increase levels of vaccination coverage. The Task Force on Community Preventive Services has conducted systematic reviews of 17 interventions designed to raise vaccination coverage levels in children, adolescents, and adults and made recommendations regarding the use of those interventions. This report provides a summary of the recommendations; informs readers of sources from which they can obtain the full review of the interventions and more detail regarding the application of the interventions at the local level; and informs readers regarding other work of the Task Force. BACKGROUND Despite the availability of safe and effective vaccines and substantial progress in reducing vaccine-preventable diseases, the delivery to and acceptance of vaccinations by targeted populations are essential to further reducing and eliminating vaccine-preventable causes of morbidity and mortality in the United States (1). The growing numbers of vaccines and complexity of vaccination schedules make delivering appropriate vaccinations in a timely manner increasingly difficult for health-care providers and health-care and public health systems (2). The recommendations included in this report are intended to guide communities in achieving or maintaining high levels of vaccination coverage and low rates of vaccine-preventable diseases. INTRODUCTION The independent, nonfederal Task Force on Community Preventive Services (the Task Force) is developing the Guide to Community Preventive Services (the Guide) with the support of the U.S. Department of Health and Human Services (DHHS) in collaboration with public and private partners. CDC provides staff support to the Task Force for development of the Guide, and CDC staff assisted in preparing this report. In addition, staff from CDC's National Immunization Program provided scientific leadership in conducting the reviews for the chapter "Vaccine-Preventable Diseases: Improving Vaccination Coverage in Children, Adolescents, and Adults." However, the recommendations presented in the chapter and this report were developed by the Task Force and are not necessarily the recommendations of either CDC or DHHS. The chapter on vaccine-preventable diseases is the first to be completed for the Guide. This report summarizes the recommendations from the Task Force, which are included in that chapter. This report also provides an overview of the process used by the Task Force to select and review evidence for the recommendations. A more complete description of the systematic reviews of effectiveness that are the foundation of the recommendations are in press (1). A full report of the recommendations and supporting evidence for the chapter will be published later in the American Journal of Preventive Medicine. That report will summarize the systematic reviews of effectiveness, the recommendations, and additional information (e.g., systematic reviews of economic evaluations, a discussion of barriers to implementation, and a summary of remaining research questions). This report and other chapter-related publications will provide guidance from the Task Force to personnel in state and local health departments and managed care organizations, purchasers of health care, those responsible for funding public health programs, and others who have interest in or responsibility for improving vaccination coverage in children, adolescents, and adults. Methods The Guide's methods for systematic reviews and linking evidence to recommendations will be described in detail elsewhere (1, American Journal of Preventive Medicine) but are described briefly in this report. In the Guide, evidence is summarized regarding a) the effectiveness of interventions; b) the applicability of effectiveness data (i.e., the extent to which available effectiveness data might apply to other populations and settings); c) other positive or negative effects of the intervention, including positive or negative health and nonhealth outcomes; d) economic consequences; and e) barriers to implementation of interventions (3). For each Guide chapter, multidisciplinary chapter development teams conduct reviews by
For the chapter on vaccine-preventable diseases, the development team evaluated selected interventions to improve coverage levels for vaccinations universally recommended for certain age groups (Table 1). For example, measles, mumps, and rubella vaccinations are recommended for young children; hepatitis B vaccinations are recommended for adolescents; and annual influenza vaccinations are recommended for adults aged greater than or equal to 65 years. The team focused on interventions that are intended to improve routine delivery of those universally recommended vaccinations. They chose not to address vaccinations with more targeted indications (e.g., vaccinations recommended for persons with specific medical conditions such as asthma or vaccinations for travelers). The major outcomes that were considered included delivery of vaccinations and the occurence of vaccine-preventable diseases. Interventions reviewed were either single-component (i.e., using only one activity) or multicomponent (i.e., more than one related activity) to achieve desired outcomes. The interventions included in the review were from a larger list and were prioritized for review by a multidisciplinary team of consultants,* which included some Task Force members. The selected interventions were chosen because they have an important impact or are widely practiced. The review evaluated 17 interventions, which were organized into three categories: a) increasing community demand for vaccinations, b) enhancing access to vaccination services, and c) provider-based interventions. Interventions were grouped together on the basis of their similarity and depth of available literature (i.e., the more literature available, the more subcategories that could be evaluated). Sometimes, the classification or nomenclature was different from that used in the original studies being reviewed. When such a discrepancy occurred, interventions were grouped according to the definitions stated in this report. Some activities that might improve vaccination coverage were not considered interventions for the purposes of this review. Activities that provide information for public health action (e.g., immunization registries) provide useful information that might incorporate or lead to interventions (e.g., client reminder/recall, provider reminder/recall, and assessment and feedback for vaccination providers). However, registries were considered to be a part of the public health infrastructure rather than interventions. Similarly, improving vaccines (e.g., developing vaccines that are less likely to cause adverse reactions or increasing numbers of antigens contained in a vaccine, thus reducing the number of injections required) can lead to improvements in vaccination coverage. However, improved vaccines are made primarily for other reasons (e.g., harm reduction or to allow the administration of more antigens than would otherwise be feasible) and are, therefore, not considered to be interventions for the purposes of the chapter on vaccine-preventable diseases. With rare exceptions (e.g., using 1998 papers for home visits and unpublished information regarding WIC** interventions), a study had to meet the following general criteria for inclusion in the reviews of effectiveness:
For each intervention reviewed, the team developed an analytic framework indicating possible links between the intervention under study and certain outcomes. The primary outcome of interest for determining effectiveness was a measure of vaccination (e.g., vaccination coverage levels or doses delivered) because the linkage between vaccination and reduction of disease, morbidity, and mortality is strong (4). Current low rates of certain vaccine-preventable diseases make using vaccination levels a more sensitive and feasible-to-measure indicator of intervention impact than using disease rates. Each study meeting the inclusion criteria was read by two reviewers who used a standardized abstraction form to record
The strength of the body of evidence of effectiveness was characterized as strong, sufficient, or insufficient on the basis of the number of available studies, the suitability of study designs for evaluating effectiveness, the quality of execution of the studies, the consistency of the results, and the effect size. Several studies need to show effects that were generally similar in size and direction for a body of evidence to be considered consistent. In addition, the overall strength of a body of evidence increases as numbers of studies increase, suitability of designs and quality of execution improve, and effect sizes increase. The Guide links evidence to recommendations using an explicit process. In general, strength of evidence of effectiveness corresponds directly to strength of recommendations (e.g., strong evidence of effectiveness corresponds to an intervention being strongly recommended, and sufficient evidence corresponds to an intervention being recommended). Other types of evidence can also affect a recommendation. For example, evidence of important harms might result in an intervention not being recommended even if it is effective. Furthermore, a recommendation might be limited to a specific population (e.g., strongly recommended for adults but insufficient evidence for children) because evidence of effectiveness is applicable to some populations and settings but not others. A determination that evidence is insufficient is important for identifying areas of uncertainty but should not be confused with evidence of ineffectiveness. A determination of insufficient evidence assists in identifying a) areas of uncertainty regarding effectiveness of an intervention and b) specific continuing research needs. In contrast, evidence of ineffectiveness leads to a recommendation that the intervention not be used. RESULTS The systematic search by the chapter development team identified 197 studies that met the inclusion criteria (1). Of these, 79 were excluded from further consideration on the basis of limitations in their execution or design and were not considered further (1). Task Force recommendations were based on the remaining 118 qualifying studies (1),*** all of which had good or fair execution and the following designs:**** Greatest Suitability for Assessing Effectiveness
Moderate Suitability for Assessing Effectiveness
Least Suitability for Assessing Effectiveness
Considerable variation existed in the numbers of studies available per intervention. For example, client reminder/recall interventions and provider reminder/recall interventions had 42 and 29 qualifying studies, respectively, whereas community education-only programs, school-based vaccination programs, and vaccination interventions in child care centers had one or no qualifying studies for evaluation. This report summarizes the interventions, findings from the reviews, and the Task Force recommendations (Table 2). USE OF THE RECOMMENDATIONS IN COMMUNITIES AND HEALTH-CARE SYSTEMS These recommendations and the reviews on which they are based will be useful for choosing interventions, but local contextual information is also important. Local context includes observed problems, community preferences and priorities, and specific interventions that are feasible and appropriate. Choosing interventions that work in general and that are well-matched to local needs and capabilities, then implementing those interventions well, is vital for improving vaccination coverage at the local level. A starting point for addressing vaccine-preventable disease problems in communities and health-care systems is to assess activities currently being performed, current levels of vaccination coverage, and information regarding vaccine-preventable disease rates. These should be compared with such relevant goals as those in Healthy People 2000 (5), Healthy People 2010 (U.S. Department of Health and Human Services, Draft for Public Comment, September 1998), and additional applicable goals developed locally. In addition to assessing overall progress towards vaccination goals, health planners should also consider whether special attention is warranted for population groups at high risk. In general, the lower the vaccination coverages and the higher the burden of vaccine-preventable diseases in a population or subgroup, the greater the need to improve coverage. For example, all vaccine-preventable diseases except tetanus are primarily spread by person-to-person contact among unvaccinated persons. Low vaccination coverage levels (6,7) and crowding can be particularly common among urban and low-socioeconomic populations. Therefore, improving coverage among persons living in poverty in urban communities should be a top priority. When improvement in vaccination coverage is needed, the causes of underimmunization should be assessed and interventions chosen that address local problems. The chapter on vaccine-preventable diseases groups interventions into categories to enable users to match interventions to problems. For example,
Once a general strategy for addressing a local problem is selected, the recommendations in the chapter can be used in conjunction with local experience to help select appropriate interventions. Recommendations and effectiveness data can be used to assess the extent to which interventions have been found to consistently improve vaccination coverage. On the basis of those data, the use of strongly recommended and recommended interventions should be increased. Information regarding applicability can be used to assess the extent to which the interventions reviewed might match a particular local situation. Economic information, though limited, can be useful in identifying interventions that meet public health goals more efficiently than other available options for reaching the same goals. Reviews and recommendations provided in the Guide need to be considered along with such local information as resource availability, administrative structures, economic, social, and regulatory environment of organizations and practitioners. Guidance for implementation is available elsewhere (8). ADDITIONAL INFORMATION REGARDING THE TASK FORCE AND THE GUIDE During 1999-2000, Guide chapters will be prepared and released as each is completed. Other chapters of the Guide will cover such topics as motor vehicle occupant injury, tobacco use, sexual behavior, cancer, sociocultural environment, and oral health. Later, a compilation of the chapters will be published in book form. Additional information regarding the Task Force and the Guide is available on the Internet at <http://web.health.gov/communityguide>. References
* Consultants for the chapter on vaccine-preventable diseases included David Atkins, M.D., M.P.H., Agency for Health Care Policy and Research, Rockville, Maryland; Joseph Chin, M.D., M.S., Health Care Financing Administration, Baltimore, Maryland; Caswell A. Evans, D.D.S., M.P.H., National Institutes of Health, Bethesda, Maryland; Theresa W. Gyorkos, Ph.D., Montreal General Hospital and McGill University, Montreal, Quebec, Canada; George J. Isham, M.D., HealthPartners, Minneapolis, Minnesota; Susan M. Lett, M.D., M.P.H., Massachusetts Department of Public Health, Boston, Massachusetts; Rose Marie Matulionis, M.S.P.H., Association of State and Territorial Directors of Health Promotion and Public Health Education, Washington, DC; Lloyd F. Novick, M.D., M.P.H., Onondaga County Health Department, Syracuse, New York; Thomas N. Saari, M.D., University of Wisconsin, Madison, Wisconsin; William Schaffner, II, M.D., Vanderbilt University, Nashville, Tennessee; and Susan C. Scrimshaw, Ph.D., University of Illinois, Chicago, Illinois. ** The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) is administered by the U.S. Department of Agriculture. *** For additional information regarding the methods or results, contact Peter A. Briss, M.D. **** A more detailed description of the methods for classifying study designs in the Guide will be published later in the American Journal of Preventive Medicine. Table 1 Note: To print large tables and graphs users may have to change their printer settings to landscape and use a small font size.
TABLE 1. Universally recommended vaccinations for children, adolescents, and adults
=============================================================================================
Population Vaccination Dosage
-------------------------------------------------------------------------------------------
All young children Measles, mumps, and rubella 2 doses
Diphtheria-tetanus toxoid 5 doses
and pertussis vaccine
Poliomyelitis 4 doses
Haemophilus influenzae 3-4 doses
type B
Hepatitis B 3 doses
Rotavirus* 3 doses before first birthday
Varicella 1 dose
Previously unvaccinated or Hepatitis B 3 doses, total
partially vaccinated
adolescents
Varicella If no previous history of
varicella, 1 dose for children
aged <12 years, 2 doses for
children aged >=13 years
Measles, mumps, and rubella 2 doses, total
Tetanus-diphtheria toxoid If not vaccinated during
previous 5 years, 1
combined booster during
ages 11-16 years
All adults Tetanus-diphtheria toxoid 1 dose administered every
10 years
All adults aged >=65 years Influenza 1 dose administered annually
Pneumococcal 1 dose
-------------------------------------------------------------------------------------------
* Because rotavirus vaccine was not universally recommended during the period considered in
this review, it is not reflected in these reviews.
=============================================================================================
Return to top. Table 2 Note: To print large tables and graphs users may have to change their printer settings to landscape and use a small font size.
TABLE 2. Selected interventions to increase vaccination coverage among children, adolescents, and adults and recommendations
from the Task Force on Community Preventive Services regarding the use of these interventions
=====================================================================================================================================================================================
Task Force
recommendation
Intervention for use Intervention description Key findings
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Increasing community demand for vaccinations
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Client reminder/ recall systems Strongly recommended Reminders that vaccinations are due (reminders) Improves vaccination coverage in children and
or late (recall) are provided to target populations. adults in several settings and populations.
Delivery techniques include telephone calls, Effective when applied in individual practice
letters, or postcards; contents of messages vary. settings, across entire communities, and across
several intervention characteristics (e.g.,
(Interventions that incorporate aspects of client reminder or recall, content, theoretical basis,
reminder/recall and home visits were classified and method of delivery).
under home visits.)
Effective whether used alone or as part of a
multicomponent intervention.
Multicomponent Strongly recommended Target populations receive education regarding Improves vaccination coverage among children
interventions that include vaccinations. and adults in both communitywide and
education clinic-based settings.
Vaccination providers might also receive
education. Effective in several contexts.
Used with at least one other activity to improve (These interventions have incorporated
vaccination rates. education with other activities, including [from
most common to least common among the
qualifying studies] client reminders, provider
education, expanded hours or access, provider
reminders, reducing out-of-pocket costs,
client-held vaccination records, WIC
interventions, medical and psychosocial
assessments, nutrition services, and home visits.
Contribution of individual components to overall
effectiveness could not be attributed.)
Vaccination requirements Recommended Laws or policies are enacted or enforced that Effective in reducing vaccine-preventable
for child care, school, require vaccinations or other documentation of disease or improving vaccination coverage in all
and college attendance immunity as a condition of attendance. relevant populations.
Differences in effectiveness of state laws based
on the law's specific characteristics or its
enforcement could not be determined.
Communitywide Insufficient evidence* Provides information to a target population in a The only qualifying study evaluated
education only (Small numbers of geographic area. effectiveness in changing vaccination delivery
qualifying studies and but had limitations in design and conduct and
limitations in their Can also provide information to vaccination found inconsistent results in different
designs and executions.) providers. subpopulations.
Does not include other features (e.g., No qualifying studies were identified that
reminders), activities, or efforts limited to evaluated effectiveness in changing knowledge
specific settings. and attitudes regarding vaccinations.
Clinic-based education Insufficient evidence* Provides information to persons served in a No studies were identified that evaluated
only (Small numbers of specific medical or public health clinical setting. strategies other than printed educational
qualifying studies and materials.
limitations in their Does not include other features (e.g., reminders)
designs and executions.) or activities provided in other settings (e.g., The only qualifying study that evaluated
school or child care centers). effectiveness of printed materials on vaccination
coverage found small and nonsignificant effects.
The two before/after studies that evaluated the
effects of vaccination information statements on
client knowledge or attitude towards vaccination
documented variable effects.
Client or family incentives Insufficient evidence* Provides financial or other incentives to Three qualifying studies were identified, and
(Small numbers of motivate acceptance of vaccinations. those studies included four intervention arms.
qualifying studies,
variability in Incentives can involve either rewards or One intervention arm that evaluated use of
interventions evaluated, penalties. incentives only found a not statistically
and variability in size and significant (6%) net change in coverage.
statistical significance of (Some interventions with aspects of incentives
results.) [e.g., WIC+ programs and vaccination The other three intervention arms evaluated
requirements for child care, school, and college incentives and reminders with and without
attendance] are categorized elsewhere.) additional activities; those findings were variable
in size and statistical significance.
Client-held medical records Insufficient evidence* Provides to clients or family members medical Four qualifying studies were identified, one of
(Small numbers of records that indicate which vaccinations have which evaluated client-held records only and
studies, limitations in been received. three of which evaluated client-held records
study design and used in combination with clinic-based education,
conduct, variability in client reminders, or multiple strategies.
interventions evaluated,
and variability in size and Effectiveness in improving vaccination coverage
statistical significance of was variable in size and statistical significance.
reported results.)
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Enhancing access to vaccination services
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Reducing out-of-pocket Strongly recommended Can include providing free vaccinations or Improves vaccination coverage in children and
costs administration, providing insurance coverage, or adults across several settings and populations.
reducing copayments for vaccinations at the
point of service. Effective when applied in individual clinical
settings, in statewide programs, or in national
efforts.
Effective whether used alone or as part of a
multicomponent intervention.
Expanding access in Strongly recommended One or more of the following: As a part of multicomponent interventions,
medical or public health as part of a Reduces the distance from the setting to the improves vaccination coverage among children
clinical settings multicomponent population. and adults in several contexts.
intervention
Increases or makes more convenient the hours The contribution of individual components to
Insufficient evidence* during which vaccination services are provided. the overall effectiveness of these interventions
when used alone cannot be attributed.
(Small numbers of Delivers vaccinations in clinical settings in which
qualifying studies and they were not provided previously Only two intervention arms evaluated expanded
limitations in their (e.g., inpatient units). access only; effect sizes were small and
designs and executions.) statistical significance variable.
Reduces administrative barriers to obtaining
vaccination services within clinics (e.g.,
"drop-in" clinics or an "express lane"
vaccination service).
Vaccination programs in Recommended Encourages the vaccination of low-income Improves vaccination coverage in children
Women, Infants, and clients of this nonmedical setting. whether used alone or as part of a
Children (WIC) settings+ multicomponent intervention.
At a minimum, requires assessment of each
child's immunization status and referral of All qualifying studies evaluated assessing the
underimmunized children to a health-care immunization status of WIC clients and either
provider. providing vaccinations on-site or referring
clients elsewhere for vaccination.
Can include education, provision of
vaccinations, and incentives to accept Some interventions also used monthly voucher
vaccinations. (e.g., more frequent WIC* visits for pick-up or provided free vaccinations.
children who are not up-to-date with their Contributions of individual components to the
vaccinations). overall effectiveness could not be determined.
Home visits Recommended Provides face-to-face services to clients in their Improves vaccination coverage.
homes.
Most available studies were conducted in
Services can include education, assessment of socioeconomically disadvantaged populations.
need for vaccinations, referral for vaccinations,
or provision of vaccinations. When applied only to improve vaccination
coverage, home visits can be highly
Can also include telephone or mailed reminders. resource-intensive relative to other available
options for improving vaccination coverage.
Vaccination programs Insufficient evidence* Intended to improve delivery of vaccinations to Only one qualifying study was identified; it did
in schools (A single qualifying study school attendees aged approximately 5-18 years. not provide comparative data regarding
and limitations in its vaccination outcomes.
design and execution.) Usually includes vaccination-related education
of students, parents, teachers, and other school
staff and either provision of vaccinations or
referral for vaccinations.
Can also include incentives to participants and
methods for acquiring written consent from
parents.
(Laws requiring vaccination for school entry are
evaluated elsewhere.)
Vaccination programs in Insufficient evidence* Encourages the vaccination of children aged <5 Only one study was identified; it did not qualify
child care centers (No qualifying studies) years. for the review.
Requires assessment of each child's
immunization status at entry into child care or at
some point during the child's enrollment.
Can also involve additional assessments at
periodic intervals, education or notification of
parents, referral of underimmunized children to
a health-care provider, or provision of
vaccinations on-site.
(Laws requiring vaccination for child care
centers are evaluated elsewhere.)
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Provider-based interventions
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Provider reminder/recall Strongly recommended Informs those who administer vaccinations that Improves vaccination coverage in adults,
individual clients are due (reminder) or overdue adolescents, and children whether used alone or
(recall) for specific vaccinations. as part of a multicomponent intervention.
Techniques by which reminders are delivered - Effective across several intervention
in client charts, by computer, by mail, or other - characteristics (e.g., computerized or simple
and content of the reminders vary. reminders, checklists, or flowcharts) and in
several settings and populations.
(Interventions that incorporate elements of
reminders and standing orders are classified as
standing orders for the purposes of the chapter
on vaccine-preventable diseases.)
Assessment and Strongly recommended Involves retrospectively evaluating the Improves vaccination coverage in adults and
feedback for vaccination performance of providers in delivering one or children whether used alone or as part of a
providers more vaccinations to a client population and multicomponent intervention.
giving this information to the providers.
Effective across several settings and populations.
Can also involve other activities (e.g., incentives
or benchmarking: comparing performance to a Specific characteristics (e.g., content, intensity,
goal or standard). use of incentives, or benchmarking) that
contribute most to effectiveness cannot be
determined from available data; however, a
variety of feedback interventions have been
consistently effective in several contexts.
Standing Orders Strongly recommended Nonphysician medical personnel prescribe or Improves vaccination coverage whether used
for adults deliver vaccinations to client populations by alone or as part of a multicomponent
Insufficient evidence* for protocol without direct physician involvement at intervention and is effective in such settings as
children the time of the interaction. hospitals, clinics, and nursing homes.
(Small numbers of
qualifying studies and Settings include clinics, hospitals, and nursing Insufficient evidence exists to assess the
limitations in their homes. effectiveness of standing orders in improving
designs and executions.) delivery of vaccinations to children because only
(Dedicated vaccination clinics often operate one qualifying study was available; that study
under standing orders, but standing orders in had limitations in design and conduct and
that context were not considered to be an reported effects not substantially different from
intervention for the purposes of the chapter on zero.
vaccine-preventable diseases.)
Provider education only Insufficient evidence* Provides information to vaccination providers to Only four qualifying studies were identified.
(Small numbers of increase their knowledge or change attitudes.
qualifying studies, Two studies of low-intensity interventions
limitations in their design Techniques can include written materials, evaluated the impact of these interventions
and conduct, and videos, lectures, continuing medical education regarding vaccination coverage; one
variability in results.) programs, and computerized software. documented small and nonsignificant impacts;
the other demonstrated that provider education
produced smaller impacts than provider
reminder/recall or standing orders.
Three studies of provider education-only
interventions documented variable impacts
regarding provider knowledge and attitudes.
The best-described and most-intensive
intervention produced improvements in provider
knowledge and attitudes.
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* A determination that evidence is insufficient should not be confused with evidence of ineffectiveness. A determination of insufficient evidence assists in
identifying (a) areas of uncertainty regarding effectiveness of an intervention and (b) specific continuing research needs. In contrast evidence of ineffectiveness
leads to a recommendation that the intervention not be used.
+ The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) is administered by the U.S. Department of Agriculture.
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