Evaluation of Measurement Reliability and Agreement of a Wearable ECG Device (HEH) Compared with a Standard ECG Device

Objectives: This study aimed to evaluate the measurement reliability and agreement of a wearable electrocardiogram (ECG) device (HEH) compared with a standard 12-lead ECG device (FX) to validate its clinical utility in Korean medicine practice.Methods: In a randomized sequential method-comparison study of 94 adults, ECG parameters were sequentially measured using both the HEH and FX devices during a single visit. Primary efficacy variables were heart rate, RR interval, and QRS interval. Secondary efficacy variables were the PR interval, QT interval, QTc interval, and axis. Inter-device reliability and agreement were assessed using the Intraclass Correlation Coefficient (ICC; two-way mixed model, absolute agreement) and Bland-Altman plots. Results: HEH demonstrated excellent reliability for the primary efficacy variables (ICC>0.90) and good reliability for the secondary efficacy variables (ICC>0.87). Bland-Altman analysis revealed that the mean difference was near zero for all variables. The mean difference for heart rate fell within the allowable limits defined by ANSI/AAMI/IEC 60601-2-27:2011. The mean differences for the QRS, PR, and QT intervals fell within the allowable limits defined by the KS C IEC 60601-2-25 CSE study criteria. Axis showed good ICC (0.876) but a relatively higher mean absolute difference (MAD=13.1°).Conclusions: The HEH device demonstrates high reliability and agreement comparable to those of the standard ECG device (FX). These findings suggest that HEH is a valid tool for long-term clinical monitoring and quantitative evaluation of treatment efficacy in Korean medicine.