Today's clinical laboratory has a diversity of reagents and protocols from which to choose: a variety of clinical chemistry reagents, antibodies, and molecular probes, among others. These materials facilitate serum and urine analysis, histology, hematology, cytology, and a host of additional sensitive and specific assays

Regardless of the application, labs may see an array of labeling statements indicating a reagent's general use: "For Laboratory Use Only" [LUO]; "For Research Use Only" [RUO]; "For Investigational Use Only" [IUO]; "For In Vitro Diagnostic Use" [IVD]; and "Analyte Specific Reagent" [ASR]. These preparations are often employed without realizing the course manufacturer's must follow in order to provide reagents, and the reasons for these designations.