TY - JOUR T1 - Longitudinal passive cough monitoring and its implications for detecting changes in clinical status JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00001-2022 VL - 8 IS - 2 SP - 00001-2022 AU - Juan C. Gabaldón-Figueira AU - Eric Keen AU - Matthew Rudd AU - Virginia Orrilo AU - Isabel Blavia AU - Juliane Chaccour AU - Mindaugas Galvosas AU - Peter Small AU - Simon Grandjean Lapierre AU - Carlos Chaccour Y1 - 2022/04/01 UR - http://openres.ersjournals.com/content/8/2/00001-2022.abstract N2 - Research question What is the impact of the duration of cough monitoring on its accuracy in detecting changes in the cough frequency?Materials and methods This is a statistical analysis of a prospective cohort study. Participants were recruited in the city of Pamplona (Northern Spain), and their cough frequency was passively monitored using smartphone-based acoustic artificial intelligence software. Differences in cough frequency were compared using a one-tailed Mann–Whitney U test and a randomisation routine to simulate 24-h monitoring.Results 616 participants were monitored for an aggregated duration of over 9 person-years and registered 62 325 coughs. This empiric analysis found that an individual's cough patterns are stochastic, following a binomial distribution. When compared to continuous monitoring, limiting observation to 24 h can lead to inaccurate estimates of change in cough frequency, particularly in persons with low or small changes in rate.Interpretation Detecting changes in an individual's rate of coughing is complicated by significant stochastic variability within and between days. Assessing change based solely on intermittent sampling, including 24-h, can be misleading. This is particularly problematic in detecting small changes in individuals who have a low rate and/or high variance in cough pattern.When compared to continuous monitoring, limiting observation to 24 h can lead to inaccurate estimates of change in cough frequency, influenced by its mean frequency and variance. This is important when evaluating small changes in cough frequency. https://bit.ly/3NtfPw1 ER -