ESSA TIERS OF EVIDENCE
Educators search for high-quality research and evidence-based interventions to strengthen grant applications, to support comprehensive and targeted schools, or to implement new programming in their schools. Evidence requirements under the Every Student Succeeds Act (ESSA) are designed to ensure that states, districts, and schools can identify programs, practices, products, and policies that work across various populations.
The What Works Clearinghouse (WWC) has valuable tools for locating studies that meet the ESSA evidence requirements. Here are the other pieces of the puzzle, including logos that can be seen throughout the WWC website to identify studies that meet ESSA requirements.
- Meets WWC Standards Without Reservations under version 2.1 or later to meet Tier 1
- Statistically significant positive effect to meet Tier 1
- At least 350 students to meet Tier 1
- At least two educational sites to meet Tier 1
Meets WWC Standards Without Reservations in most cases means that a study was a randomized controlled trial (RCT) that was deemed by experts to be well-designed and well-implemented and that did not have problems with attrition (that is, participants dropping out or otherwise leaving the study).
- Meets WWC Standards With or Without Reservations under version 2.1 or later to meet Tier 2
- Statistically significant positive effect to meet Tier 2
- At least 350 students to meet Tier 2
- At least two educational sites to meet Tier 2
Meets WWC Standards With Reservations means that a study has some potential issues that require caution. It may be a strong quasi-experimental study (meaning that it did not have random selection and/or assignment of participants) with comparison groups that are similar at the baseline. It may also be an RCT that is not as well implemented or has issues with attrition.
The WWC includes tools to assist state and local administrators, teachers, and others in finding research that meets the definitions of strong (Tier 1) or moderate(Tier 2) evidence under ESSA. This video describes how to use these tools as well as the criteria the WWC uses to define strong and moderate evidence.
The WWC practice guides provide recommendations that can help teachers, administrators, and other educators improve student outcomes. The WWC characterizes the level of evidence for each recommendation as "strong," "moderate," or "minimal". These infographics map the practice guide recommendations for elementary and secondary practice guides to the evidence definitions used by the Department of Education.
Use the Reviews of Individual Studies search tool to find individual studies that have been reviewed by the WWC with study findings categorized into ESSA evidence tiers. For more information, please watch the video above.
NOTE: Under ESSA, for a state/district/school to consider an intervention as a Tier 1 evidence-based practice, the setting AND samples from the studies used to determine the evidence tier must overlap with the population AND setting of the state/district/school interested in implementing the intervention.
For a state/district/school to consider an intervention as a Tier 2 evidence-based practice, the setting OR the samples from the studies used to determine the evidence tier need to overlap with setting OR population.