PMC

Receiver operator curves (ROC) comparing Model 1 (influence factors: age, gender, BMI, hypertension, diabetes, and hyperlipidemia) with Model 2 (influence factors and relative spectral energy values) for predicting coronary artery disease. Area under curve (AUC) of Model 1 and Model 2 is 0.788 and 0.856, respectively.

Measurements were performed by researcher using pulse diagnostic instruments after participants had rested quietly in the examination room for 10 minutes. Pulse measurements were performed on the radial arteries of the wrists on both arms, with the right arm followed by the left. In this study, the measurement position we selected was the most prominent position of the pulsation at the wrist radial artery, which corresponded to the styloid process of the radius. The graphical demonstration of the measurement position of the pulse is shown in Figures and . Prior to measuring, we first located the most distinct section of radial artery pulsation and marked it, then positioned the pressure probe on the marking, slowly pressing down until the pulse had emerged to ensure there were no errors in positioning. We then continued to press the pressure probe vertically downward until the pulse with the highest amplitude appeared before recording the measurement. Using the recording mode of the PDS-2010 Skylark Pulse Analysis System, each arm was continuously recorded for 6 s. The analog signals were converted into digital data and stored for further pulse spectrum analysis.