A reporting checklist for human and animal heart rate variability research.

Heart rate variability (HRV) is widely used as a non-invasive marker of cardiac autonomic regulation in human and experimental animal research. Its accessibility, repeatability, and applicability across clinical, psychophysiological, wearable, and preclinical settings make HRV a valuable translational tool. However, HRV indices are highly sensitive to physiological and methodological context, including recording duration, signal quality, respiratory pattern, posture, behavioral state, circadian timing, medication use, anesthesia, temperature, species, strain, artefact correction, frequency-band selection, and analytical method. Human HRV standards provide a strong methodological foundation, but they cannot be directly transferred to animal models without considering species-specific differences in basal heart rate, respiratory frequency, autonomic regulation, recording conditions, and experimental constraints. In animal studies, additional sources of heterogeneity include telemetry versus surface ECG recordings, conscious versus anesthetized states, handling and restraint, surgical recovery, body temperature control, and inconsistent frequency-domain definitions. This review synthesizes current methodological knowledge on HRV measurement in human and experimental animal studies and highlights major challenges that limit reproducibility and translational interpretation. Attention is given to common methodological pitfalls, and the risk of overinterpreting single indices such as LF/HF as direct measures of sympathovagal balance. We also propose a minimum reporting framework for human and experimental animal HRV studies, with shared translational items intended to support authors, reviewers, and editors. Transparent reporting of acquisition, preprocessing, analysis, and physiological context may improve comparability across studies and strengthen the role of HRV as a bridge between mechanistic animal research and human autonomic assessment.Clinical trial number: not applicable.