Changes

It is possible to read one paper about Quell principles right on the official Quell website, but this doesn't contain necessities of independent scientific studies. Although there are no studies dealing with Quell product specifically, but several independent researches about transcutaneous electric nervous stimulation were made. These studies seem to be not so unambiguous when speaking about good efficacy of TENS in treatment. Here follow few works engaged in TENS technology and its influence on different deseases.Sluka and Walsh<ref>Sluka KA, Walsh D., Transcutaneous electrical nerve stimulation: basic science mechanisms and clinical effectiveness, in: Journal of Pain, 2003, p. 109-121</ref> summarize existing researches of TENS.,