This guideline outlines specimen requirements; performance criteria; algorithms for the potential use of sequential or duplicate testing; recommendations for intermethod comparisons of immunological test kits for detecting infectious diseases; and specifications for development of reference materials.This document is no longer being reviewed as part of the CLSI consensus process. However, because of its usefulness to a limited segment of the healthcare community, CLSI is continuing to make the document available for its informational content.This document is available in electronic format only.