Sungjoon Hong, Christina Hartnett, Michael Ruane, Jason Tagliarino, Michael Nizich, M. Toma
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引用次数: 0
Abstract
Background
Machine learning (ML) applications in clinical medicine are vulnerable to data leakage, particularly temporal leakage from post-diagnostic features and patient-level leakage from improper partitioning, compromising electrocardiogram (ECG) abnormality detection systems. This study addresses these vulnerabilities through patient-level data splitting and systematic evaluation across multiple classification scenarios.
Methods
ECG data from 4419 observations representing 2180 unique patients were analyzed using Random Under-Sampling Boosting (RUSBoost). Three binary classification scenarios were defined: Scenario 1 (Abnormal vs. Normal, excluding borderline), Scenario 2 (Abnormal + Borderline vs. Normal), and Scenario 3 (Abnormal vs. Normal + Borderline). Patient-level stratified partitioning (60:20:20) prevented information leakage. Models were evaluated using accuracy, sensitivity, specificity, F1-score, learning curves, and precision-recall curves across all partitions.
Results
Scenario 1 demonstrated optimal generalization with test accuracy of 70.79%, sensitivity of 60.30%, specificity of 86.50%, and F1-score of 0.712, exhibiting monotonic decline across partitions (73.98%→71.50%→70.79%). Scenario 2 achieved 65.26% test accuracy with greater degradation (6.17 percentage points), reflecting increased difficulty when borderline cases were grouped with abnormal findings. Scenario 3 exhibited problematic non-monotonic patterns (71.84%→67.71%→69.36%) with premature convergence, indicating fundamental generalization challenges despite near-balanced classes (1.07:1 ratio).
Conclusions
Aggregate metrics alone inadequately support clinical deployment decisions. Medical AI evaluation must examine learning dynamics, generalization stability, and precision-recall calibration across partitions. Process-focused standards assessing monotonic decline, convergence characteristics, and calibration stability are essential for reliable ECG abnormality detection deployment.
期刊介绍:
The ANNALS OF NONINVASIVE ELECTROCARDIOLOGY (A.N.E) is an online only journal that incorporates ongoing advances in the clinical application and technology of traditional and new ECG-based techniques in the diagnosis and treatment of cardiac patients.
ANE is the first journal in an evolving subspecialty that incorporates ongoing advances in the clinical application and technology of traditional and new ECG-based techniques in the diagnosis and treatment of cardiac patients. The publication includes topics related to 12-lead, exercise and high-resolution electrocardiography, arrhythmias, ischemia, repolarization phenomena, heart rate variability, circadian rhythms, bioengineering technology, signal-averaged ECGs, T-wave alternans and automatic external defibrillation.
ANE publishes peer-reviewed articles of interest to clinicians and researchers in the field of noninvasive electrocardiology. Original research, clinical studies, state-of-the-art reviews, case reports, technical notes, and letters to the editors will be published to meet future demands in this field.