Subject characteristics from previously published studies from which prediction equations were made [57, 106, 107]
| Males | Females | Combined | |
| Subjects | 248 | 242 | 490 |
| Age years | 44±17 (18–93) | 45±18 (18–87) | 44±17 (18–93) |
| Weight kg | 76.7±9.4 (55.0–105.0) | 61.6±8.8 (44.0–95.0) | 69.3±11.8 (44.0–105.0) |
| Height cm | 176±8 (154–196) | 164±7 (147–182) | 170±10 (147–196) |
| Body mass index kg·m-2 | 24.7±2.5 (18.9–29.9) | 23.0±3.0 (17.2–29.8) | 23.8±2.9 (17.2–29.9) |
| DLNO mL·min−1·mmHg−1 | 164±31 (67–235) | 119±25 (47–186) | 142±36 (47–235) |
| DLCO mL·min−1·mmHg−1 | 34.1±6.3 (11.9–49.9) | 25.1±5.3 (11.3–38.6) | 29.6±7.4 (11.3–49.9) |
| DMCO mL·min−1·mmHg−1 | 161±39 (72–250) | 104±26 (33–182) | 133±44 (33–250) |
| VC mL | 78±16 (25–121) | 65±15 (30–105) | 72±17 (25–121) |
| DMCO/VC ratio min−1·mmHg−1 | 2.11±0.57 (1.01–4.03) | 1.63±0.40 (0.88–2.96) | 1.90±0.57 (0.88–4.03) |
| KCO mL·min−1·mmHg−1·L−1 | 4.9±0.8 (2.7–7.1) | 4.8±0.7 (3.0–6.8) | 4.9±0.8 (2.7–7.1) |
| KNO mL·min−1·mmHg−1·L−1 | 23.8±3.9 (13.7–34.2) | 22.8±3.2 (13.5–31.5) | 23.3±3.6 (13.5–34.2) |
| DLNO/DLCO ratio | 4.83±0.40 (3.83–5.82) | 4.74±0.39 (3.85–5.78) | 4.79±0.40 (3.83–5.82) |
Data are presented as n or mean±sd (range). The alveolar–capillary membrane diffusing capacity for carbon monoxide (DMCO) and total volume of blood in the lung capillaries exposed to alveolar air (VC) values reported in these studies [57, 106, 107] have been recalculated according to the parameters listed in table 4. DLNO: diffusing capacity of the lung for nitric oxide; DLCO: diffusing capacity of the lung for carbon monoxide; KCO: rate of uptake of carbon monoxide from alveolar gas; KNO: rate of uptake of nitric oxide from alveolar gas.