Wheezes, crackles, rhonchi: Agreement among members of the ERS task force on lung sounds

Background The ERS Task Force on lung sounds was set up in 2012 to establish a repository of audiovisual recordings of lung auscultation for the standardization of nomenclature. We report agreement among the six members of the Task Force on the first 16 recordings. Methods Various adventitious sounds in recordings of lung sounds of 15 seconds duration from 10 children and 6 adults were classified according to recommended English language nomenclature 1 plus the category of rhonchi. Identification by respiratory phase thus offered 10 non-exclusive choices. Kappa statistics was used on pairs of raters to calculate mean Kappa per sound. Results On average there were 2.1 adventitious sounds per rater and patient (range 0.33-3.5). Complete agreement (Kappa=1) was found for 3/10 sounds in 3 of the 15 pairs of raters (fine expiratory crackles and coarse inspiratory and expiratory crackles). Mean Kappa for these were 0.21, 0.31 and 0.33, respectively (fair agreement). The mean Kappa for all ten sounds was 0.20 There was better agreement when merging the inspiratory and expiratory sounds, with a mean Kappa of 0.29. When merging fine and coarse crackles in the analysis and also high-pitched wheezes, low-pitch-wheezes and rhonchi, while still distinguishing between inspiratory and expiratory sounds, the mean Kappa was 0.45 (moderate). Conclusion Only fair interrater agreement was found when 10 different sounds were registered in 16 cases with multiple adventitious sounds. Better agreement was obtained when similar sounds were combined. 1 ACCP-ATS Joint Committee on Pulmonary Nomenclature. Chest 1975; 67:583-93.