Fig 1. Examples of patients who were excluded.

Patients for whom at least one of the programs could not generate results at all were excluded from the analysis. (A) Program 3 could not recognize right middle lobe (arrow) in this 57 year-old patient with FEV1 = 24% due to unsuccessful lobar segmentation. (B) A 50 year-old patient with FEV1 = 20% had incorrect outline of the lung and could not be processed normally in program 3. (C) Program 4 included part of the central airway to right upper lobe (arrow) in this 75 year-old patient with FEV1 = 44%. Program 3 also failed in lobar segmentation for the same patient. FEV1 = forced expiratory volume in 1s.