A novel method for automatic standardization of digital electrocardiographs

It is crucial to assure the quality of ECG recordings to support correct clinical interpretation. This research aimed at developing an automated standardization method to gauge digital electrocardiography (EC) devices. The proposed microprocessed gauge equipment (MGE) is divided into digital and analogic circuits, and embedded software to control them. Conditioned reference signals (CRS) from Physionet Bank were embedded in the MGE to simulate cardiac activity. The outputs from the MGE (or EC) are then compared with the CRS. All circuits of the MGE are gauged at the self-check mode. CRS are sent to the EC when set at the EC check mode. A commercial EC equipment was used in the MGE validation (IEC60601-2-51:2005), assessed with the statistical R² correlation analysis and Kolmogorov-Smirnov (KS). At the MGE self-test, temperature and humidity were changed (R²≥0.99 as designed). The KS test (P<;0.01) resulted in D=0.012 for amplitude accuracy, 0.0028 for timing accuracy and 0.021 for signal stability against noise influence. All KS values were lower than their respective critical values according to the default standard (5%). Finally, visual inspection between EC signals and CRS on printed graph paper at a standard scale certifies the EC reliability.