Improved repeatability of 12-lead ECG analysis using continuous scoring techniques

This study describes a method for improving the day-to-day and minute-to-minute repeatability of the deterministic computer-assisted diagnosis of left ventricular hypertrophy. Conventional upper limits of normal for many age-dependent electrocardiographic parameters have been replaced by continuous equations, thereby, eliminating points of discontinuity that can contribute to lack of repeatability. Estimates of the normal amounts of variability present in many electrocardiographic parameters that are used in the diagnosis of left ventricular hypertrophy are calculated. These estimates are then used together with a smoothed version of a score function to form the basis of the new technique. The implementation of smoothing techniques enhances the repeatability of the Glasgow electrocardiographic analysis program. With respect to the electrocardiographic diagnosis of left ventricular hypertrophy, these methods eliminate 44% of the day-to-day and 50% of the minute-to-minute inconsistencies in computer reports.