Variables | Sensitivity | Specificity | Positive Predictive Value | Negative Predictive Value |
---|---|---|---|---|
Entire cohort | ||||
FVC % predicted, n = 265 | ||||
< 80 (conventional and optimal) | 0.69 | 0.73 | 0.86 | 0.49 |
DLCO % predicted, n = 214 | ||||
< 60 (conventional) | 0.58 | 0.70 | 0.82 | 0.41 |
< 62 (optimal) | 0.60 | 0.70 | 0.83 | 0.42 |
< 70 (alternative) | 0.80 | 0.51 | 0.80 | 0.52 |
< 80 (alternative) | 0.92 | 0.32 | 0.77 | 0.63 |
Combination of PFT thresholds % predicted, n = 214 | ||||
FVC < 80 and DLCO < 60 | 0.46 | 0.81 | 0.85 | 0.38 |
FVC < 80 or DLCO < 60 | 0.79 | 0.57 | 0.82 | 0.53 |
FVC < 80 and DLCO < 62 | 0.49 | 0.81 | 0.86 | 0.40 |
FVC < 80 or DLCO < 62 | 0.80 | 0.56 | 0.81 | 0.53 |
FVC < 80 and DLCO < 65 | 0.53 | 0.78 | 0.85 | 0.41 |
FVC < 80 or DLCO < 65 | 0.82 | 0.46 | 0.78 | 0.52 |
FVC < 80 and DLCO < 70 | 0.61 | 0.76 | 0.86 | 0.45 |
FVC < 80 or DLCO < 70 | 0.87 | 0.43 | 0.78 | 0.57 |
FVC < 80 and DLCO < 80 | 0.66 | 0.73 | 0.85 | 0.47 |
FVC < 80 or DLCO < 80 | 0.94 | 0.27 | 0.76 | 0.65 |
Autoantibody Scl-70–positive patients | ||||
FVC < 80, n = 78 | 0.75 | 0.05 | 0.98 | 0.05 |
DLCO < 60, n = 62 | 0.70 | 1.00 | 1.00 | 0.10 |
FVC < 80 or DLCO < 60, n = 62 | 0.85 | 0.50 | 0.98 | 0.10 |
Autoantibody Scl-70–negative patients | ||||
FVC < 80, n = 183 | 0.63 | 0.73 | 0.78 | 0.57 |
DLCO < 60, n = 150 | 0.50 | 0.68 | 0.70 | 0.48 |
FVC < 80 or DLCO < 60, n = 150 | 0.74 | 0.57 | 0.72 | 0.60 |
FVC ≥ 80% and DLCO ≥ 60% predicted represent traditional normal cutpoints based on 95% CI in healthy population. PFT: pulmonary function test; FVC: forced vital capacity.