Analyzing false positives (defined as cases of indicating a sound class when this class was not indicated in the standard- this is the sum of all the incorrect selections that were not in the given sample, with the individual sound classes being treated independently of each other) the graph shows no differences between groups, except for the prolonged expiratory phase - the only sound class with statistically significant differences (chi2 (4) = 13.1, p = 0.011). This difference can be found in the results obtained by pulmonologists and students.
In the next step, the responses were grouped using the main classes proposed by the European Respiratory Society (ERS) (Pasterkamp et.al, 2016). In practice, this meant that if the participant had indicated any of the subgroups shown in Table 3 and any of them was marked as the correct one in the standard, the answer was treated as a correct one. In the case of the vesicular breath sound or the bronchical one, no other answer that is not part of the subgroup could be concurrently marked. In this way, five main classes of sounds were created.