Comprehensive Signal Quality Evaluation of a Wearable Textile ECG Garment: A Sex-Balanced Study

Maximilian P. Oppelt; Tobias S. Zech; Sarah H. Lorenz; Laurenz Ottmann; Jan Steffan; Bjoern M. Eskofier; Nadine R. Lang-Richter; Norman Pfeiffer

arXiv · 2508.21554

Comprehensive Signal Quality Evaluation of a Wearable Textile ECG Garment: A Sex-Balanced Study

Maximilian P. Oppelt·Tobias S. Zech·Sarah H. Lorenz·Laurenz Ottmann·Jan Steffan·Bjoern M. Eskofier·Nadine R. Lang-Richter·Norman Pfeiffer

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Abstract

We introduce a novel wearable textile-garment featuring an innovative electrode placement aimed at minimizing noise and motion artifacts, thereby enhancing signal fidelity in Electrocardiography (ECG) recordings. We present a comprehensive, sex-balanced evaluation involving 15 healthy males and 15 healthy female participants to ensure the device's suitability across anatomical and physiological variations. The assessment framework encompasses distinct evaluation approaches: quantitative signal quality indices to objectively benchmark device performance; rhythm-based analyzes of physiological parameters such as heart rate and heart rate variability; machine learning classification tasks to assess application-relevant predictive utility; morphological analysis of ECG features including amplitude and interval parameters; and investigations of the effects of electrode projection angle given by the textile / body shape, with all analyzes stratified by sex to elucidate sex-specific influences. Evaluations were conducted across various activity phases representing real-world conditions. The results demonstrate that the textile system achieves signal quality highly concordant with reference devices in both rhythm and morphological analyses, exhibits robust classification performance, and enables identification of key sex-specific determinants affecting signal acquisition. These findings underscore the practical viability of textile-based ECG garments for physiological monitoring as well as psychophysiological state detection. Moreover, we identify the importance of incorporating sex-specific design considerations to ensure equitable and reliable cardiac diagnostics in wearable health technologies.

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Maximilian P. Oppelt, Tobias S. Zech, Sarah H. Lorenz, Laurenz Ottmann, Jan Steffan, Bjoern M. Eskofier, Nadine R. Lang-Richter, Norman Pfeiffer. 2025-08-29. Comprehensive Signal Quality Evaluation of a Wearable Textile ECG Garment: A Sex-Balanced Study. https://arxiv.org/abs/2508.21554

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