“…Pulmonary function tests (PFT) as assessment tools were reported in 40 studies ( 5 , 13 , 15 – 18 , 20 – 24 , 27 , 28 , 30 – 36 , 38 – 45 , 49 , 52 – 54 , 56 , 57 , 59 , 60 , 62 – 64 , 69 ), and included spirometry, measurement of diffusion capacity and assessment of static lung volumes (i.e., total lung capacity (TLC), and residual volume (RV)). Two studies reported PFT abnormalities as potential diagnostic criteria for CVID-ILD in addition to CT ( 64 , 65 ).…”