Table 3:

Performance Characteristics of Pulmonary Function Tests for the Detection of Interstitial Lung Disease

PFT Parameters	N	Sensitivity	Specificity	PPV	NPV	Positive LR	Negative LR	FPR	FNR
FVC < 80%	212	63%	68%	70%	61%	2.0	0.5	0.32	0.37
TLC < 80%	146	46%	77%	74%	51%	2.0	0.7	0.23	0.54
DLCO < 80%	200	80%	51%	66%	68%	1.6	0.4	0.49	0.20
FVC or DLCO < 80%	199	85%	42%	64%	70%	1.5	0.4	0.58	0.15
FVC or TLC or DLCO < 80%	143	85%	42%	68%	66%	1.5	0.4	0.58	0.15

PFT = pulmonary function test; FVC = forced vital capacity; TLC = total lung capacity; DLCO = diffusion capacity for carbon monoxide; PPV = positive predictive value; NPV = negative predictive value; LR = likelihood ratio; FPR = false positive rate; FNR = false negative rate