Passage: The window period is the time from infection until a test can detect any change. The average window period with HIV-1 antibody tests is 25 days for subtype B. Antigen testing cuts the window period to approximately 16 days and nucleic acid testing (NAT) further reduces this period to 12 days.Performance of medical tests is often described in terms of:

Question: What does antigen testing do?
Antigen testing cuts the window period to approximately 16 days