This home test works just like a pregnancy test - one line means negative, two lines means positive. The test can be performed on materials, including fabric, swabs, and bodily fluids.
This test looks for a protein called prostate-specific antigen (PSA), not found in any other bodily fluids except minute amounts in blood, urine and some female bodily fluids.
A positive result indicates the presence of PSA, suggesting the presumptive presence of semen. Confirm results with a DNA test.