ECG exercise test: (1) has differential diagnostic value for atypical chest pain with coronary artery disease, and negative results help to negate the diagnosis of coronary artery disease. However, for young and middle-aged women positive results do not confirm the diagnosis of coronary artery disease, with false positives up to 40%.　　(2) For patients with typical angina pectoris, a negative result cannot negate the diagnosis. Positive results help to diagnose and determine the value of the degree and extent of ischemia.