A radio frequency (RF) instrument may include a method of classifying a tissue in live time. The method may include activating the instrument for a first period of time T1 when the RF instrument contacts the tissue, plotting at least three electrical parameters associated with the tissue to classify the tissue into distinct groups, and applying a classification algorithm to classify the tissue into a distinct group in live time. The parameters may include an initial impedance of the tissue, a minimum impedance of the tissue, and an amount of time that the impedance slope is ∼0. The instrument may collect the parameters during a predetermined amount of time, such as within the first 0.75 seconds of the activation of the device. The classification algorithm may include a support vector machine algorithm that may use a linear, polynomial, or radial basis set.
