About this Database Background Methods Rating Scales Choosing Your Strategy Sources Health Conditions & Diseases Acknowledgements Contact Us Disclaimer Search Policies & Programs

Display All Policies & Programs

Using Evidence Ratings

Evidence of effectiveness can help inform a ‘short list’ of strategies to consider more closely in your community. The stronger the evidence of effectiveness, the more certain you can feel that a strategy will work, and often, the farther you can stretch your resources.

A strategy rated Scientifically Supported has stronger evidence of effectiveness than a strategy rated Some Evidence which, in turn, has stronger evidence than a strategy rated Insufficient Evidence or Expert Opinion. Strategies with each of these ratings are often more likely to work than those rated Mixed Evidence, and always more likely to work than those rated Evidence of Ineffectiveness.

Strategies rated Mixed Evidence have been shown not to work in some circumstances, and require careful consideration before implementing. Strategies rated Evidence of Ineffectiveness have consistently been shown not to work and are simply not good investments. You can learn more about how we assign ratings here.

The less robust the body of evidence supporting a strategy’s effectiveness, the more important it is to evaluate the effects of that strategy and share your results. Evaluation and information sharing can help others learn from your community’s experience and strengthen the evidence base going forward.


Understanding the body of evidence in your area of interest can help inform decisions about when to implement ‘tried and true’ strategies and when to be more innovative. When deciding whether to implement tried and true strategies, it is helpful to consider:

Innovation is an important approach to problem solving—all strategies rated Scientifically Supported were, at one time, untested ideas. When you decide to be innovative, understanding what has been shown to work and what hasn’t can help ensure that your creative approaches will succeed. Evaluating these approaches, and sharing your results with others, can help build successful strategies for the future.

Community Context

Whether you are considering a ‘tried and true’ strategy or a more innovative approach, it is important to consider your community’s culture, priorities, and resources along with evidence of effectiveness. For example:

Involving a broad group of stakeholders, including local data and subject matter experts and members of the community you want to serve, can help you select the best strategy for your community.