A method of selecting one or more assay electrodes for use in a device used in an electrical thoracic scan system. The device has a linear multielectrode array, and the method includes providing a device for use in an electrical thoracic scan system. The device includes: a band having an inner surface and a linear array of electrodes arranged along the length of the band and on the inner surface for contacting the skin surface. Further, each electrode is selectively connectable to a control unit. The method also includes: placing the device on the chest of the subject designating, as reserve electrodes for potential use, the electrodes making contact with the skin surface selecting a plurality of assay electrodes from the reserve electrodes and utilizing the assay electrodes in an electrical thoracic scan process.
