The What Works Clearinghouse (WWC) Procedures and Standards Handbooks (version 4.0) provides reviewers with a detailed description of the procedures and standards used by the WWC in the review of studies and production of reports. While the Handbooks address most situations, reviewers occasionally need additional guidance. The WWC has produced a guidance document for reviewers to provide clarification and interpretation of standards and support consistency across reviews. This guidance document does not articulate any changes to the procedures and standards in the version 4.0 Handbooks. Rather, the guidance document clarifies how the standards should be implemented in situations where the current Handbooks are not sufficiently specific to ensure consistent reviews.

The guidance document is provided here to inform WWC readers on the additional guidance provided to reviewers applying version 4.0 procedures and standards. Guidance can change based on future WWC Statistical, Technical, and Analysis Team work and feedback from the Institute of Education Sciences and others. Revised guidance will be shared with WWC reviewers and will be updated on the WWC website.