Who can be assigned as an RPR? RPR test measures substances proteins called antibodies that are present in the blood of people who may have syphilis.
With this approach, a positive enzyme immunoassay EIA or chemiluminescence immunoassay CIA test is followed by further testing with a nontreponemal test—often referred to as reverse screening Figure 2.
A negative or nonreactive result means you don't likely have syphilis.