An Introduction to the Science

Interventions and evidence based practices that are poorly implemented – or not implemented at all – do not produce expected health benefits. Even when effectively implemented, interventions and practice changes still might not produce expected health benefits if effectiveness is lost during implementation, or if the intervention or practice was never effective in the first place.

Implementation science is the scientific study of methods and strategies that facilitate the uptake of evidence-based practice and research into regular use by practitioners and policymakers.

The field of implementation science seeks to systematically close the gap between what we know and what we do (often referred to as the know-do gap) by identifying and addressing the barriers that slow or halt the uptake of proven health interventions and evidence based practices.

Defining Implementation Science

As it is a fairly new field of study, there are many published definitions of implementation science which range from narrow to broad. Some definitions emphasize closing the know-do gap, where others emphasize producing generalizable knowledge or locally fit solutions. Examples of the range of definitions include:

  • Glasgow, Eckstein, and ElZarrad (2013): Implementation science is the "application and integration of research evidence in to practice and policy."
  • Allottey et al (2008): Implementation science is “applied research that aims to develop the critical evidence base that informs the effective, sustained and embedded adoption of interventions by health systems and communities.”
  • Peters et al (2013): Implementation science is "the scientific inquiry into questions concerning implementation — the act of carrying an intention into effect, which in health research can be policies, programmes, or individual practices (collectively called interventions).”
  • National Institutes of Health, National Cancer Institute: "Implementation science is the study of methods to promote the adoption and integration of evidence-based practices, interventions, and policies into routine health care and public health settings to improve the impact on population health."

The Implementation Science Program in the UW Department of Global Health sees the fundamental question of implementation science as: How do we get ‘what works’ to the people who need it, with greater speed, fidelity, efficiency, quality, and relevant coverage? This inclusive stance values the systematic application of research methods from a range of diverse disciplines that are seen as critical for understanding the process, context, and outcomes of implementation, with an end goal of enabling scale-up and population-level benefits. Although not exhaustive, the DGH Implementation Science Program embraces ten main research methods for implementation science, as defined here.

Overlapping fields of study

There are several other newly emerging fields of science that overlap with implementation science, including improvement science, knowledge translation, program science, and delivery science. The main distinction between these highly related fields is their main focus.

Improvement science “deploys rapid tests of change to guide the development, revision and continued fine-tuning of new tools, processes, work roles and relationships” and is “a methodology for using disciplined inquiry to solve a specific problem of practice” (Carnegie Foundation).

The focus of improvement science is narrower than implementation science, as it seeks to maximize the impact of lessons learned from a specific improvement effort with the intent to maximize local benefits from local solutions.

Delivery science has a broad focus compared to implementation science, targeting health systems strengthening and addressing the societal factors that impact public policy and system functioning.

Knowledge translation is “the ‘exchange’, ‘synthesis’, and ethically sound ‘application’ of researcher findings with a complex system of relationships among researchers and knowledge users,” (Khalil, 2016). Where knowledge translation differs from implementation science is that it does not cover how to implement knowledge.

Program science is focused on “the totality of a program, including an appraisal of the epidemic transmission dynamics, setting appropriate prevention objectives by sub-population, selecting and combining interventions and allocating resources between interventions accordingly” (Program Science: The Concept and Applications). Implementation science focuses on the uptake of an evidence-based practice into programmatic settings, but not on improvement of a whole program in and of itself.

Distinguishing implementation science from intervention research

Implementation science differs from intervention research in that it focuses on the strategies used to implement evidence based practices, rather than on intervention effectiveness.

Typical implementation science foci

Aim: To evaluate an implementation strategy
Intervention: Directed at clinician behavior, and/or organizational practice change
Outcomes: Acceptability, adoption, appropriateness, feasibility, fidelity, implementation cost, penetration, and sustainability
Unit of analysis and randomization: The clinician, team, facility, or organization


Learn More:

WATCH: Implementation Science: An Introductory Workshop for Researchers, Clinicians, Policy Makers and Community Members

Presented by the Center for Prevention Implementation Methodology at Northwestern University

WATCH: The Development of Implementation Science & Future Directions

Presented by the NIH National Cancer Institute