Cough Intensity: A Novel Measure of Cough Burden

by | Dec 11, 2025 | Whitepaper

This whitepaper explores an important but historically under-measured dimension of cough burden: cough intensity. While cough frequency is the traditional metric used to objectively measure cough burden, it is limited in its ability to capture only how often a patient coughs and not the qualitative dimensions of those coughs such as how burdensome or forceful they were. In recent years there has been increased commentary on the need for multidimensional assessments of cough burden that extend beyond frequency alone.1

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Why Cough Intensity Matters

Cough intensity describes the strength, forcefulness, or severity of individual coughs and cough bouts. Patients often report their most distressing coughs not by how frequently they occur, but by how “strong,” “violent,” or exhausting they feel. Two patients with similar cough frequencies may experience vastly different symptom severity and quality-of-life impact due to the quality of the coughs themselves.

Recent studies have begun to validate intensity as a meaningful additional objective measure to cough frequency.2 Measures such as cough sound amplitude or chest motion may offer additional insight into the intensity of individual coughs, potentially improving insight in research and clinical trials.

Patient Voice: The Burden of Intense Coughing

Qualitative research shows that intense coughs are tightly linked to physical strain, breathlessness, difficulty expectorating, prolonged coughing fits, and complications such as pain, dizziness, or exhaustion. Patients consistently describe intense coughs as particularly disruptive, reinforcing the value of measures that reflect this experience.3

How Cough Sound Intensity Is Quantified

A commonly used metric, peak RMS amplitude, captures the explosive energy of a cough sound, serving as a practical surrogate for cough sound pressure level. However, accurate measurement requires stable acoustic pathways. Wearables that rely on open-air microphones (e.g., smartwatches) are prone to major variability due to changes in distance, angle, clothing, and environmental noise.

By contrast, torso-adhered acoustic sensors minimize these sources of error. Because cough vibrations travel consistently through the chest wall, a body-adhered sensor provides a fixed, reproducible sound transmission pathway ideally suited for capturing cough intensity.

Recent Publications on Cough Intensity Using the Strados Labs RESP® Biosensor

Multiple publications in 2025 have demonstrated the feasibility and value of measuring cough intensity with the RESP® Biosensor:

  • Feasibility of Cough Sound Intensity (PFF Summit 2025):
    Cough amplitude was reliably quantified in over 31,000 coughs, showing distinct patterns from cough frequency and remaining stable across 24-hour cycles. View publication
  • Cough Intensity Characterizing Bouts (American Cough Conference 2025):
    Coughs within bouts exhibited significantly higher intensity, consistent with patient reports that bouts are among the most severe and burdensome aspects of their cough. View publication
  • Cough Intensity in Chronic vs. Subacute Cough (ERS 2025):
    Cough intensity during bouts differed dramatically between chronic and subacute cough populations, suggesting potential value for stratifying disease severity and burden. View publication

Implications for Clinical Trials and Future Research

Cough intensity represents an important advancement toward a multidimensional, patient-centered understanding of cough burden. Future work will expand beyond acoustic amplitude by integrating chest motion data, biomechanical effort, and temporal patterns to create a more complete and clinically actionable picture of symptom severity.

References

  1. Smith T. FDA panel votes against gefapixant for unexplained chronic cough. Healio. 2023. Available at: https://www.healio.com/news/pulmonology/20231117/fda-panel-votes-against-gefapixant-for-unexplained-chronic-cough. Accessed October 3, 2025.
  2. Lee KK, Matos S, Evans DH, White P, Pavord ID, Birring SS. A longitudinal assessment of acute cough. ERJ Open Res. 2017;3(2):00160-2016. doi:10.1183/23120541.00160-2016. [PMCID: PMC5501240]
  3. Kum, E., Guyatt, G. H., Muñoz, C., Beaudin, S., Li, S.-A., Abdulqawi, R., Badri, H., Boulet, L.-P., Chen, R., Dicpinigaitis, P., Dupont, L., Field, S. K., French, C. L., Gibson, P. G., Irwin, R. S., Marsden, P., McGarvey, L., Smith, J. A., Song, W.-J., O’Byrne, P. M., & Satia, I. (2022). Assessing cough symptom severity in refractory or unexplained chronic cough: findings from patient focus groups and an international expert panel. ERJ Open Research, 8(1), 00667-2021. https://doi.org/10.1183/23120541.00667-2021

Authors

Jason Kroh
Chief Technology Officer, Strados Labs

Tom deLaubenfels, PhD
Director of Data Science, Strados Labs