A method and system for extracting important signal information is disclosed. The method examines a group of signals obtained from testing of a patient's nervous system and finds a signal area of interest. Once a cluster of signals that all have the area of interest is found - the system concludes that the area of interest is located and validated. Signals that are not within the cluster are rejected and the signals within the cluster are signal-averaged to yield a signal-averaged waveform. The signal averaged waveform represents the results of the test.