Fat causes impedance or resistance to the signal. Conventional Bioelectrical Impedance Analysis methods are accurate, though not as convenient as the Tanita BIA method, and may be somewhat subjective based on the placement of electrodes. The user must be in a horizontal position while electrodes and conductive jelly are placed on a wrist and ankle. This procedure is usually performed in a physician's office or clinic. Most conventional BIA manufacturers use hydrostatic weighing as the reference method.
Measurements are very repeatable when tests are performed under consistent conditions.
The equipment is not expensive, making Tanita a professionally-accepted method that can be adapted easily for home use. Skinfold measurements taken by calipers are easy to do, inexpensive, and the method is portable. The quality of the calipers is also a factor. Inexpensive models sold for home use are usually less accurate than those used by an accredited technician. Many people find calipers to be uncomfortable and invasive.