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).
The TB skin test. The TB skin test may be used to find out if you are infected with TB bacteria. You can get a skin test at the health department or at your doctorâs office. A health care worker will inject a small amount of testing fluid (called tuberculin or PPD) into the skin on the lower part of your arm.he TB skin test may be used to find out if you are infected with TB bacteria. You can get a skin test at the health department or at your doctorâs office. A health care worker will inject a small amount of testing fluid (called tuberculin or PPD) into the skin on the lower part of your arm.