Methods and systems are directed to the evaluation of a particular healthcare activity by comparing the plurality of waves of the healthcare activity from two or more of the same healthcare activity. This includes the electrocardiogram (ECG or EKG) and its use in comparing two or more ECGs of a patient. Two or more different ECG tracings are overlaid in order to compare them directly. Physicians also have the ability to time-shift one or more of the waves forward or backward in time so that relevant points on the waves line up and better correlate with the other corresponding waves. The ECG tracings and the waves are displayed on a graphical user interface (GUI).
