An automated age detection system employing a patient monitoring lead assembly and a patent monitoring device. In operation, the patient monitoring lead assembly conducts electrical activity of a heart of a patient to the patient monitoring device. In response thereto, the patient monitoring device classifying the patient as an adult patient or a pediatric patient as a function of electrocardiogram feature(s) derived from electrocardiogram measurement(s) of the electrical heart activity. The patient monitoring device may further estimate the age as a function of electrocardiogram feature(s). The classification facilitates an appropriate application of an adult analysis or a pediatric analysis of the electrical heart activity.
