An ever-expanding evidence base, detailing programs and policies that have been scientifically evaluated and proven to work, is available to public health practitioners. The practice of evidence-based public health (EBPH) is an integration of science-based interventions with community preferences for improving population health (
1). The concept of EBPH evolved at the same time as discourse on evidence-based practice in the disciplines of medicine, nursing, psychology, and social work. Scholars in these related fields seem to agree that the evidence-based decision-making process integrates 1) best available research evidence, 2) practitioner expertise and other available resources, and 3) the characteristics, needs, values, and preferences of those who will be affected by the intervention () (
2-
5).
Public health decision making is a complicated process because of complex inputs and group decision making. Public health evidence often derives from cross-sectional studies and quasi-experimental studies, rather than the so-called "gold standard" of randomized controlled trials often used in clinical medicine. Study designs in public health sometimes lack a comparison group, and the interpretation of study results may have to account for multiple caveats. Public health interventions are seldom a single intervention and often involve large-scale environmental or policy changes that address the needs and balance the preferences of large, often diverse, groups of people.
The formal training of the public health workforce varies more than training in medicine or other clinical disciplines (
6). Fewer than half of public health workers have formal training in a public health discipline such as epidemiology or health education (
7). No single credential or license certifies a public health practitioner, although voluntary credentialing has begun through the National Board of Public Health Examiners (
6). The multidisciplinary approach of public health is often a critical aspect of its successes, but this high level of heterogeneity also means that multiple perspectives must be considered in the decision-making process.
Despite the benefits and efficiencies associated with evidence-based programs or policies, many public health interventions are implemented on the basis of political or media pressures, anecdotal evidence, or "the way it's always been done" (
8,
9). Barriers such as lack of funding, skilled personnel, incentives, and time, along with limited buy-in from leadership and elected officials, impede the practice of EBPH (
8-
12). The wide-scale implementation of EBPH requires not only a workforce that understands and can implement EBPH efficiently but also sustained support from health department leaders, practitioners, and policy makers.