A method of detecting whether a localization element is within or outside of an introducer sheath generally includes obtaining a localization signal from the localization element and detecting the state of the localization element relative to the sheath based upon the quadrature component of the localization signal. A baseline quadrature component is typically established with the localization element outside of the sheath. When the quadrature component deviates from this baseline value, it is indicative of the localization element being within the sheath. Conversely, when the quadrature component remains relatively close to the baseline value, it is indicative of the localization element being outside of the sheath. In an electrophysiology study, the state information can be used to take corrective action with respect to the data being collected.