Table of Contents

• Purpose Statement (p. 1-2)
• Literature Search (p. 2)
• Screening of Research Using Eligibility and Relevance Criteria (pp. 2-5)
• Synthesis and Dissemination of Findings (p. 6)
• Appendix A. Search, Screening, and Prioritization of Research (pp. 7-9)
• Appendix B. Search Terms Used in Literature Search (p. 10-12)
• Appendix C. Databases Used in Literature Search (pp. 13)

Protocol Details

• Version: 4.1
• Released: November 2024

What is a Protocol?

Starting in January 2021, the What Works Clearinghouse (WWC) uses the Study Review Protocol in combination with the Procedures and Standards Handbook to guide reviews of all studies. In particular, the Study Review Protocol provides additional information on eligible outcome domains for all topic areas reviewed by the WWC and provides examples of outcome measures that fall within each domain.

When conducting systematic reviews, the WWC uses the Study Review Protocol to review studies and an accompanying topic area synthesis protocol to define the parameters of the systematic review. The synthesis protocol provides criteria for the literature search; guidance on how to identify and prioritize relevant studies for review and inclusion in evidence synthesis products; and guidance on intervention, sample, and outcome eligibility criteria for the synthesis.

Prior to 2021, studies were typically reviewed using a topic-specific synthesis protocol and the corresponding version of the Procedures and Standards Handbook. In addition to defining the parameters for the review, these protocols described any topic-specific applications of the design standards, such as how to establish baseline equivalence between samples when required.