IFS is an effective pain management therapy as muscle stimulators go.  It is far superior to TENS for the treatment of deep, chronic intractable pain.

Because it requires a sine waveform (most all home units are square waveforms) and  4 electrodes for true interferential (interference current) which is an overlapping of a carrier frequency with a beat frequency, it is difficult to gauge, without a vector scanner, how much of the actual overlapping currents are effecting the application area.

It is felt that interferential is most effective in the clinical setting and enhanced with a home unit.