Table 4. Reference equations for spirometry.
| Models | Sex | Indices | Reference equations |
|---|---|---|---|
| Choi's7 | Men | FVC | −4.8434 − 0.00008633 × age2 + 0.05292 × height + 0.01095 × weight |
| FEV1 | −3.4132 − 0.0002484 × age2 + 0.04578 × height | ||
| Women | FVC | −3.0006 − 0.0001273 × age2 + 0.03951 × height + 0.006892 × weight | |
| FEV1 | −2.4114 − 0.0001920 × age2 + 0.03558 × height | ||
| Present | Men | FVC | −4.38775 − 0.01184 × age + 0.05547 × height |
| FEV1 | −2.40147 − 0.02134 × age + 0.04103 × height | ||
| Women | FVC | −3.09063 + 0.003904 × age + 0.038694 × height | |
| FEV1 | −1.32933 − 0.00872 × age + 0.02762 × height |
FVC = forced vital capacity, FEV1 = forced expiratory volume in 1 second.