How Accurate Are Rats Tests?
WouterRats can be very sensitive and specific, but the question is how accurate are they? The results of studies comparing RATs to traditional methods reveal that they are not completely accurate. A RAT test is most accurate if it detects both positive and negative specimens. RATs are sensitive to the presence of both asymptomatic and symptomatic organisms, but they can be inaccurate if the specimen is not positive or negative.
There are several factors that affect RAT accuracy. The number of asymptomatic individuals in a population can affect the results. The test may miss two to seven percent of cases if there are no symptoms. Positive predictive values for populations with higher viral loads can vary widely. In addition, the sample type and storage conditions may affect RAT accuracy.
The TGA has developed a three-category sensitivity rating. The higher the sensitivity, the less likely it is to miss a positive. The highest sensitivity category covers 91-95% of positive cases. The next category, acceptable, covers 81%-90% of positive cases. The category with the lowest sensitivity is low sensitivity.
While RATs are extremely sensitive, they are not completely accurate. For example, a RAT can miss 50 percent of cases with higher viral loads. Therefore, RATs should not be relied on in one-off testing. But if you need to be sure, it’s worth trying.
