Genecand, Léon; Service de Pneumologie, Hôpitaux Universitaires de Genève, Genève, Switzerland.;
Jaksic, Cyril; Desponds, Roberto; Simian, Gaëtan; et al
Physiological reports,2025 Mar
- he dispersion of the tidal volume and of the breathing frequency have been used to diagnose dysfunctional breathing during cardio-pulmonary exercise testing. No validated methods to objectively describe this dispersion exist. We aimed to validate such a method. We used simulations based on real-life parameters. Moving standard deviation (MSD) and residuals from locally estimated scatterplot smoothing (LOESS) were evaluated. The precision and the bias of each tested method at rest and during exercise simulations, with and without sighs, were measured. For LOESS, a 2nd degree polynomial was used, and different spans were tested (LOESS 1 , LOESS 0.75 , and LOESS 0.5 ). For MSD, different number of points used for the calculation were tested (MSD 7 , MSD 11 , MSD 15 , and MSD19). The LOESS method was globally more precise, had less bias, and was less influenced by the trend as compared to MSD in almost all simulations except for extremely low dispersion combined with extreme trends. LOESS 0.75 had intermediate bias and precision between LOESS 0.5 and LOESS 1 in all simulations. LOESS 0.75 is a method that combines high precision, low bias, and low influenceability of trends. It could be considered as the method of choice to evaluate the dispersion of breathing parameters during cardiopulmonary exercise testing.
- (© 2025 The Author(s). Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)