The E-meter, originally the electropsychometer, is an electronic device for displaying the electrodermal activity (EDA) of a human being. It is used for auditing in Scientology and divergent groups. The efficacy and legitimacy of Scientology's use of the E-meter has been subject to extensive litigation and in accordance with a federal court order, the Church of Scientology publishes disclaimers declaring that the E-meter "by itself does nothing," is incapable of improving health, and is used specifically for spiritual purposes.