Diabetes was the seventh leading cause of death in the United States in 2006; approximately 233,619 deaths were attributed to the disease (1). In 2007, an estimated 23.6 million people had diabetes, representing 7.8% of the US population (1). Of these, 17.9 million cases were diagnosed, leaving 5.7 million people unaware they had diabetes. Another estimated 57 million adults aged 20 years or older had prediabetes in 2007, putting them at increased risk for diabetes (1).

The US Department of Health and Human Services launched the National Diabetes Education Program (NDEP) in 1997 to improve diabetes management and to help reduce the morbidity and mortality from diabetes and its complications. The leading federal government program that promotes diabetes prevention and control, NDEP is cosponsored by the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health (NIH) and the Division of Diabetes Translation of the Centers for Disease Control and Prevention (CDC). The aim of NDEP is to improve the treatment of diabetes and its complications, to promote early diagnosis, and to prevent the onset of diabetes (2). To reach these goals, NDEP has formulated the following program objectives:

Engaging stakeholders is central to establishing a common frame of reference about the program and the key evaluation questions to be asked, and to ensuring that the evaluation findings are used for program improvement. In designing its evaluation, NDEP involved members of its partnership network, which includes the leading national organizations of health professionals and volunteers concerned about diabetes, state diabetes prevention and control programs, community health professionals and organizations concerned about diabetes, and representatives from private industry. Members of the Partnership Network participate in NDEP's Steering and Operations committees and in the program's 10 work groups. NDEP engaged key stakeholders in several ways.

In the CDC framework, a consensus program description helps develop the evaluation focus, associated indicators, and data sources. A strong, comprehensive program description also integrates the planning and evaluation process, as was the case for NDEP.

NDEP's program description emerged from an extensive review of the literature on health behavior research on diabetes and from strategic planning meetings with experts in diabetes education and representatives of stakeholder groups. The review of the literature and the strategic planning meetings provided direction for developing the program's first strategic plan (NDEP, unpublished data, 1997). The plan formulated a statement of need for the program and presented key objectives, target audiences, messages, strategies, and tactics it would employ.

The NDEP Evaluation Work Group provided guidance on developing outcome measures for evaluating the program by prioritizing a 3-tiered list of outcome measures for each target audience. From the list of prioritized outcome measures, the work group developed a conceptual program evaluation framework that included an overview of program resources, program activities, process goals, and intermediate and long-term goals (Figure 1).

The evaluation work group and staff used the conceptual framework to develop the more explicit logic model. For example, in looking at the program's glucose control component, the conceptual framework enabled NDEP to develop a logic model that included key strategies to increase knowledge, influence attitudes and beliefs, and change behaviors through its mass media messages and educational materials and activities. As shown in Figure 2, the framework allowed NDEP to specify the intended intermediate and long-term outcomes the program was seeking related to blood glucose control among people with diabetes.

As a national education program, NDEP focuses its evaluation efforts on monitoring and assessing what the program's mass media campaigns, educational materials, and other promotional activities can plausibly influence; for example, increasing knowledge of the importance of controlling risk factors for cardiovascular disease in people with diabetes, improving a person's feeling of self-efficacy to take charge of diabetes self-management, or increasing the practice of self-monitoring of blood glucose levels. At the same time, NDEP monitors long-term outcomes, such as prevention of diabetes-related complications, by tracking incidence and prevalence of blindness, kidney failure, amputations, and cardiovascular disease as reported by the National Health Care Surveys conducted by CDC's National Center for Health Statistics (NCHS). The program monitors intermediate outcomes, such as the health status of people with diabetes who have major risk factors that contribute to diabetes complications, using data from the National Health and Nutrition Examination Survey (NHANES) and the National Health Interview Survey (NHIS) conducted by NCHS and CDC's Behavioral Risk Factor Surveillance System (BRFSS). NDEP monitors these trends and uses the results to determine what messages and educational activities the program needs to emphasize.

The outcomes specified in the NDEP evaluation lend themselves to survey data collection. Because of budget and regulatory constraints on survey research by federal government programs, NDEP devised a multifaceted approach for measuring program outcomes using survey data. The program uses a combination of existing data available from ongoing federal government and partner organization surveys related to diabetes and supplements these data by conducting its own survey research.

NDEP reports the results of its process and outcome evaluations to program stakeholders in many ways. One is through NDEP's annual report on evaluation activities and the latest data on outcome measures, which is presented to the program's steering committee. A summary of this report is incorporated into the steering committee meeting minutes, which are disseminated to the entire partnership network. Similarly, a report on NDEP evaluation is included on the agenda of the partnership network's meetings held every 2 years.

The results of the Partner Activities Survey are compiled and disseminated to all members of the partnership network. For example, recent surveys indicate that most partners who respond to these semiannual surveys conduct activities to promote NDEP's awareness campaigns. Many of them exhibit at conferences and meetings, participate in health fairs, make presentations, or conduct training sessions and workshops to promote NDEP's messages and materials. Nearly all the partners promote NDEP's Web site resources to their colleagues and constituents.

The survey reports also provide data on partner activities to the various work groups, who use the information to assess progress in implementing their strategic plans. NDEP has begun preparing process measure reports on media placements and publications dissemination related to each work group's strategic plan. For example, the report to the Hispanic/Latino work group provides process measures on all of the public service announcements and article placements, the number of Spanish-language publications distributed by the program's clearinghouse, and the number of Web downloads of Spanish-language materials.

In 2001 and 2004, NDEP completed and disseminated progress reports on the program's accomplishments, covering 1997 through 2003. To mark NDEP's 10-year anniversary, the program released a 1997-2007 report in September 2007 (7). This report presented the latest available outcome data on NDEP's priority campaigns and summarized process measures regarding media activities, publications dissemination, and Web site usage. These reports provide members of the partnership network and other NDEP constituents with information about where the program has been and where it is headed.

These 3 examples illustrate that people with diabetes have a better understanding of diabetes and are taking steps to control it:

To inform the diabetes, health professional, and public health communities about NDEP's activities, accomplishments, and lessons learned, NDEP writes and submits journal articles. NDEP staff members and partners make presentations about the program at health professional and public health meetings. The program has been on the agenda of periodic prevention summits of the US Department of Health and Human Services, where representatives have had the opportunity to address public health professionals about NDEP's activities and progress.

NDEP uses the evaluation activities and reports to assess progress toward reaching program goals and to make midcourse corrections in program activities. NDEP also updates strategic plans, including those for each work group, every 3 years. Program staff members work closely with each work group to review previous plans, assess the latest outcome and process measures, and then develop updated plans for the next 3-year period.

NDEP updates its data as new data from NHANES, NHIS, and BRFSS become available each year. The program has created a database for tracking results from these surveys and charting trends on key intermediate outcomes. These trend data are reviewed and shared with the evaluation work group, the executive committee, and the operations committee to keep them abreast of changes in outcome measures. NDEP also used the data to help set priorities and allocate program resources for messages and campaigns that need to be reinforced and disseminated to selected target audiences. Similarly, results of the NDEP survey of the public's knowledge, attitudes, and practices related to diabetes are assisting NDEP in understanding its target audiences, specifically people with diabetes, people with prediabetes, and people at risk for diabetes, and to inform the program of key issues to consider in program planning.

NDEP analyzes the results of the semiannual Partner Activities Survey to determine what, if any, changes are needed in program operations to better serve partners' needs. The Partner Activities Survey also has provided insights about the role partners play in promoting and disseminating NDEP messages and what gaps the national program staff needs to fill.

The CDC Framework for Program Evaluation in Public Health is an effective tool for structuring an evaluation process that has a high probability of producing findings that programs can use for improvement. It has given the NDEP a roadmap for asking key evaluation questions and for identifying practical solutions to obtaining answers. The process also has been helpful in educating NDEP's funders, partners, and other stakeholders regarding useful, feasible, appropriate, and accurate measures for evaluating a multifaceted public and professional education program such as NDEP, which is significantly different from a randomized clinical trial or preintervention/postintervention study, the research model that is more familiar to stakeholders.

Engaging stakeholders in the design and implementation of NDEP's evaluation has been a critical strategy. Without the support, guidance, and contributions of the many individuals and organizations that have been involved in the evaluation process, NDEP would have many more gaps in its evaluation framework.

Developing a logic model of the program and identifying the essential evaluation measures needed to assess program outcomes has helped to streamline the evaluation design and eliminate many irrelevant measures. As the program evolves, NDEP will add new components to the logic model, building on previous elements.

Most importantly, NDEP has taken to heart the iterative nature of evaluation as represented by the CDC framework. The true value of this approach for NDEP will be its attention to continuous refinement of the program's efforts based on evaluation findings — that is, closing the loop between data and action.