The xTAG RVP Assay (RVP) is a multiplexed nucleic-acid based mol. test capable of detecting 20 viruses and subtypes simultaneously in a single patient sample. In the ongoing clin. multi-center study, the RVP assay is being evaluated against direct immunofluorescence assay (DFA)/culture test methods prospectively using nasopharyngeal (NP) swab samples collected at each clin. site. Specimens were collected from individuals undergoing routine respiratory virus testing during the 2005/2006 flu season. Clin. studies indicate greater detection rates with RVP, as compared to DFA/culture. Anal. studies support the versatility and robustness of the RVP assay, as well as its ability to meet design requirements. Reproducibility studies at multiple sites with different extraction methods, days testing, and RVP lots for all targets gave an expected call percentage of 98.3%. LoD studies support the superior anal. sensitivity of the assay when it is compared with DFA and culture.