Table 2.
Validity of restrictive spirometric pattern (RSP) in relation to true pulmonary restriction
| Restrictive spirometric pattern (RSP) | True pulmonary restriction | |||
|---|---|---|---|---|
| TLC < LLN5 (Quanjer) (n = 46) |
TLC < LLN5 (Gothenburg) (n = 53) |
|||
| Value | 95% CI | Value | 95% CI | |
| RSPLLN (n = 33) | ||||
| Sensitivity | 0.33 | 0.20–0.48 | 0.34 | 0.20–0.46 |
| Specificity | 0.98 | 0.97–0.99 | 0.98 | 0.97–0.99 |
| PPV | 0.45 | 0.28–0.64 | 0.55 | 0.36–0.72 |
| NPV | 0.97 | 0.97–0.95 | 0.96 | 0.95–0.97 |
| LR+ | 17.0 | 9.2–31.5 | 21.1 | 11.3–39.4 |
| LR- | 0.69 | 0.56–0.84 | 0.67 | 0.55–0.81 |
| RSP0.7 (n = 31) | ||||
| Sensitivity | 0.30 | 0.18–0.46 | 0.32 | 0.28–0.60 |
| Specificity | 0.98 | 0.98–0.97 | 0.98 | 0.97–0.99 |
| PPV | 0.45 | 0.27–0.64 | 0.55 | 0.36–0.73 |
| NPV | 0.97 | 0.95–0.98 | 0.96 | 0.95–0.97 |
| LR+ | 16.8 | 8.8–31.9 | 21.3 | 11.1–40.9 |
| LR- | 0.71 | 0.59–0.86 | 0.69 | 0.57–0.83 |
| RSPPREDIL (n = 33) | ||||
| Sensitivity | 0.30 | 0.18–0.46 | 0.36 | 0.23–0.50 |
| Specificity | 0.98 | 0.97–0.99 | 0.98 | 0.97–0.99 |
| PPV | 0.42 | 0.25–0.61 | 0.58 | 0.39–0.75 |
| NPV | 0.97 | 0.95–0.98 | 0.96 | 0.95–0.98 |
| LR+ | 15.0 | 8.1–28.0 | 23.8 | 12.7–44.9 |
| LR- | 0.71 | 0.59–0.86 | 0.65 | 0.53–0.80 |
Definition of abbreviations: LLN Lower limit of normal; total lung capacity, PPV Positive predictive value, NPV Negative predictive value, LR+ Positive likelihood ratio, LR- Negative likelihood ratio