XVII. CDC Partners and Public Health Information and Surveillance Systems
CDC works with many partners throughout the United States and the world. State and local health departments provide the infrastructure on which the public's health is built. Other traditional partners include individuals and institutions that educate and promote the health of Americans of all ages, such as school systems, local community groups, businesses, and voluntary and professional associations and other federal organizations. In view of the increasingly diverse and complex role of public health, CDC has reached out to newer and less traditional public health partners, including churches, local organizations, health insurance organizations, health alliances, health boards, consumer groups, and private medical providers.
CDC and its partners are concerned with a wide spectrum of health issues including infectious diseases, chronic conditions, reproductive outcomes, environmental health, occupationally related health events, and injuries. This array of issues requires a variety of intervention strategies for populations, in addition to the need to provide clinical preventive services for individuals. To implement effective interventions, CDC engages in extensive dialogue with its partners, communities, and the public to identify and implement intervention strategies specific to the needs of diverse populations. Some examples include the provision of prophylactic measures (e.g., vaccination, post-exposure rabies prophylaxis), educational services (e.g., public health messages to diverse populations, counseling, and prophylaxis for contacts of persons with certain infectious diseases), inspection of food establishments, and control of outbreaks. For these activities, the rational development of public health policy depends on public health information.
In order to effectively respond to this variety of health problems and intervention methods, different types of information for action and a broad array of data collection methods are necessary. For example, information on the age of children with vaccine-preventable diseases has been used to establish policy on appropriate ages for having vaccinations. Information on the prevalence of elevated lead in blood has been used as the justification for eliminating lead from gasoline and for documenting the effects of this intervention, and information on the rate at which breast cancer is detected has led to new policies regarding the recommended ages at which to have mammograms.
As outlined in this section, CDC has a wide range of health data systems that provide the science base for identifying health problems, designing interventions, and monitoring program performance. These data systems face considerable challenges in addressing each of these three areas. For the most part, data systems that were designed to support scientific objectives are now becoming important for the monitoring of performance. Several specific challenges in providing data to monitor performance under GPRA are outlined below:
- As GPRA measures are refined over time, data systems will need to produce data on a more timely basis, and with a frequency relevant to the periods over which performance is being measured.
- As the health system itself changes, it can no longer be assured that historical data series will continue to produce needed data. For example, the move toward managed care may make medical information increasingly proprietary, making access for research and statistical purposes more difficult. Similarly, changes in relationships between different health care providers, as well as laboratories, may make public health surveillance based on case reports more difficult. At the same time, these changes present opportunities for new partnerships to obtain needed information.
- Data systems will need to produce information in sufficient quality and precision to detect what may be relatively small changes in key performance indicators. This may require investments in larger sample sizes for surveys, new technology for improving data quality, etc. Continuing research will be required to establish the data systems, as well as the underlying evaluation approaches, for assessing cause (program intervention) and effect (outcomes) for performance monitoring.
- Many of our current major national data systems are the source of GPRA measures for CDC and for other health programs. It is important to assure that these data systems are assessed and upgraded to remain current with the needs of our public health infrastructure. Resources to assure that these data systems are maintained and strengthened are included in the FY 2000 CDC budget request and need to be continued.
- Many CDC and HHS programs are implemented at the state and local level, and it will be increasingly important to obtain reliable, systematic data at these levels to monitor program implementation, performance, and outcomes.
Ascertaining what information is needed and how to collect it is a complex issue. Information for action must be useful to public health programs a local, state, and national levels. At least seven categories of information are used by CDC and its partners to understand and address disease, injury, and disability using the public health model. These categories of information include: a) reports of health events affecting individuals; b) vital statistics on the entire population; c) information on the health status, risk behaviors, and experiences of populations; d) information on potential exposure to environmental agents; e) information on existing public health programs; f) information useful to public health but obtained by organizations not directly involved in public health practice; and g) information on the health care system and the impact of the health care system on health.
Reports of Health Events. Reports of cases of specific diseases of public health importance serve as the basis of many of CDC programs. The National Notifiable Disease Surveillance System (NNDSS) seeks reports on all cases of more than 40 conditions in the United States. To minimize the burden placed on those who report the information, CDC limits the amount of information collected for each case. NNDSS data are used to monitor trends in disease, to evaluate public health programs, and to identify unusual occurrences of conditions that may require further epidemiologic investigation at the local level. For some public health purposes, effective action requires additional detail on each case.
For this reason, supplemental data collection systems have been developed for some of the diseases involved in the NNDSS. Such supplemental systems may be less comprehensive in terms of the population represented but provide more detailed information on characteristics of the occurrence of disease. For example, cases of hepatitis are reported weekly to NNDSS for publication in the Morbidity and Mortality Weekly Report (MMWR). In addition, the Viral Hepatitis Surveillance Project collects data on specific risk factors for different types of viral hepatitis in selected geographic areas. These data have been used to document the importance of behavior associated with sexual activity and drug use as a risk factor for transmitting Hepatitis B and to target education and vaccination programs.
State public health laboratories currently analyze 41 million specimens annually. Some of the data from the analyses immediately enter the electronic Public Health Laboratory Information System (PHLIS) and are used in monitoring both short and long range trends in the incidence of disease.
Intervention and control of some conditions require more detailed information than can be obtained feasibily from a large group of clinicians or institutions. As a result, networks of selected health care providers have been organized to meet these targeted information needs. For example, CDC's Sentinel Event Notification System for Occupational Risks (SENSOR) targets select groups of health care providers as a component of a comprehensive approach that uses multiple data sources to provide information used on directing efforts to prevent workplace-related morbidity. The National Nosocomial Infections Surveillance System (NNIS) receives reports from a selected group of hospitals on the incidence and characteristics of hospital-acquired infections; data from this system have been instrumental in alerting health authorities to the emergence of antibiotic-resistant strains of bacteria, which in turn has led to the development of specific recommendations regarding the use of antibiotics.
Vital Statistics. Vital records (e.g., births, deaths) are the primary source of some of the most fundamental public health information. Data on teen births, access to prenatal care, maternal risk factors, infant mortality, causes of death, and life expectancy are examples of the staples of public health provided by vital statistics. Vital statistics are often the most complete and continuous information available to public health officials at the national, state, and local levels; the timely availability of these data is critically important.
In the United States, the legal authority for vital registration rests with the States and territories. Therefore, CDC's National Center for Health Statistics (NCHS) produces national vital statistics by collecting data from the vital records of the states. NCHS works with the states to ensure a uniform national data base through the promotion of standard data collection forms, data preparation and processing procedures, and also provides partial financial support for the state systems.
Information on Health Status, Risk Factors, and Experiences of Populations. Since the determinants of many important health problems are behavioral, environmental, genetic or from other causes, health agencies need information that is not readily available from medical records on the prevalence of various types of behavior and on access to care. Thus, regularly conducted surveys of the general population are needed for public health. These surveys may range from large-scale assessments of the general population to assessments targeted at high-risk (i.e., particularly vulnerable populations). This need is particularly acute at the state and local level. Surveys provide information on
- Baseline health status (e.g., the National Health and Nutrition Examination Survey, NHANES, and the National Health Interview Survey, NHIS)
- Morbidity (e.g., the National Ambulatory Medical Care Survey, NAMCS)
- Prevalence of specific behavioral risk factors (e.g., the Behavioral Risk Factor Surveillance System, BRFSS, and the Youth Risk Behavioral and Surveillance System, YRBSS) and medical risk factors (e.g., NHANES and Pregnancy Risk Assessment and Monitoring System, PRAMS)
- Use of health care services and identification of under served populations (e.g., NHIS)
- Potential for exposure to toxic agents (e.g., the National Occupational Exposure Survey, NOES).
This information is used in developing prevention and control programs and in ensuring adequate delivery of health services.
Information on Potential Exposure to Environmental Agents. Information on exposures to environmental agents can be used in evaluation the risk to health represented by non-infectious diseases, injuries, and certain infectious diseases. For example, measurement of airborne particulates is useful in assessing risks related to certain pulmonary disorders (e.g., asthma and lung cancer). Information on vectors that may carry agents of infectious disease (e.g., ticks as vectors for Lyme disease, and Rocky Mountain spotted fever, mosquitoes as vectors for viral encephalitides, and raccoon as vectors for rabies) is important in evaluating the risk for having such infections.
Information on Programs. Data necessary to operate public health programs include such items as number of clients served and cost of services rendered. These data are useful to public health officials in assessing the effectiveness of public health programs, comparing different programs, documenting the need for continuing a particular program, and maintaining accountability for tax dollars spent.
Information from Other Organizations. Data useful for public health are currently or potentially available from organization whose function may not be related to those of CDC and of state and local health departments. Data from the Bureau of the Census, for example, are necessary both for the reliable computation or rates and for the proper adjustment of rates for comparison over time or in different geographic areas. The Environmental Protection Agency (EPA) compiles environmental air-monitoring data to assess compliance with standards for air pollutants established by the Clean Air Act. Data collected through this system are also used by public health officials for hazard alerts when pollutants exceed Federal standards and in studies of the effects of air pollutants on morbidity associated with respiratory diseases. The Occupational Safety and Health Administration (OSHA) and the Bureau of Labor Statistics compile data on the occurrence of work-related injuries and illnesses and exposure to hazards in the workplace, which can be used for surveillance and research purposes. The Department of Transportation operate the Fatal Accident Reporting System, used in public health to assess risk factors for motor-vehicle-related injuries and deaths. The Federal Bureau of Investigation (FBI) crime statistics assist in evaluating the public health impact of intentional injuries, and the Consumer Product Safety Commission collects data on injuries related to consumer products.
Information on the Heath Care System. Information is also needed on the health care system and the impact that changes in the system have on health. CDC provides a great deal of information to monitor the capacity of the personal health care system utilization of that system and access to health insurance and services by the American people. These data include: inventories of health care providers; surveys to determine patterns of utilization of health services such as hospitalization rate and uptake of new technologies tracking health insurance coverage on the part of the population and health insurance benefits provided by employers; and access to health care and barriers (both financial and non-financial) to access.