What is the difference between a biopsy and a HAIRCHECK test?

A hair biopsy or rather a scalp biopsy takes a small piece of your scalp out with a knife or punch, and sends it off to pathology to view it under a high powered microscope after it has been prepared and stained. A HAIRCHECK instrument tests for the thickness of the hair in a defined area of the scalp. As this can be compared area by area, the differences always reflects loss of hair bulk or hair mass. The HAIRCHECK test is non-invasive while the biopsy is invasive