In medicine and statistics, gold standard test is usually diagnostic test or benchmark that is the best available under reasonable conditions. Other times, gold standard is the most accurate test possible without restrictions. Both meanings are different because for example, in medicine, dealing with conditions that would require an autopsy to have a perfect diagnosis, the gold standard test would be the best one that keeps the patient alive instead of the autopsy.
Youâll use intermediate strength (5 T.U.) PPD in a tuberculin syringe that has a 1/2-inch, 26- or 27-gauge needle. Make sure the bevel edge of the needle is facing up, and insert the needle beneath the skin (Figure 1).ouâll use intermediate strength (5 T.U.) PPD in a tuberculin syringe that has a 1/2-inch, 26- or 27-gauge needle. Make sure the bevel edge of the needle is facing up, and insert the needle beneath the skin (Figure 1).
Blood tests may be used to confirm or rule out latent or active tuberculosis. These tests use sophisticated technology to measure your immune system's reaction to TB bacteria. QuantiFERON-TB Gold in-Tube test and T-Spot.TB test are two examples of TB blood tests. These tests require only one office visit. A blood test may be useful if you're at high risk of TB infection but have a negative response to the skin test, or if you've recently received the BCG vaccine.