contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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(a)Identification. A platelet factor 4 radioimmunoassay is a device used to measure the level of platelet factor 4, a protein released during platelet activation by radioimmunoassay. This device measures platelet activiation, which may indicate a coagulation disorder, such as myocardial infarction or coronary artery disease.
(b)Classification. Class II (performance standards).