Subjects’ characteristics of the combined NHANES 2009–2012 (14,349 adults; 5964 children) and pulmonary function testing characteristics
| Age group | Children | Adults | |||
| Gender | Male | Female | Male | Female | |
| N | 3042 | 2922 | 7182 | 7167 | |
| Age (years) | Mean | 11.3 | 11.5 | 43.8 | 44.6 |
| Median (IQR) | 11.0 (6.0) | 11.0 (6.0) | 45.0 (30.0) | 45.0 (29.0) | |
| Height (cm) | Mean | 151.4 | 148.2 | 176.3 | 162.5 |
| Median (IQR) | 147.0 (36.0) | 148.3 (27.1) | 174.7 (10.5) | 161.2 (9.9) | |
| Weight (kg) | Mean | 50.1 | 47.9 | 88.4 | 75.6 |
| Median (IQR) | 43.9 (31.9) | 43.7 (27.8) | 83.5 (24.8) | 72.0 (25.1) | |
| Body mass index (kg/m2) | Mean | 20.7 | 21.0 | 28.4 | 28.6 |
| Median (IQR) | 19.3 (7.0) | 19.7 (6.9) | 27.5 (7.2) | 27.9 (9.4) | |
| Body surface area (m2) | Mean | 1.4 | 1.4 | 2.0 | 1.8 |
| Median (IQR) | 1.3 (0.6) | 1.4 (0.5) | 2.0 (0.3) | 1.8 (0.3) | |
| FEV1 (L) | Mean | 2.70 | 2.41 | 3.71 | 2.70 |
| Median (IQR) | 2.21 (1.73) | 2.18 (1.30) | 3.53 (1.18) | 2.58 (0.95) | |
| FEV1 (% predicted NHANES III) | Mean | 72 | 82 | 94 | 96 |
| Median (IQR) | 67 (22) | 77 (23) | 95 (20) | 97 (19) | |
| FEV1 (% predicted GLI) | Mean | 100 | 100 | 94 | 95 |
| Median (IQR) | 101 (19) | 102 (17) | 95 (20) | 97 (19) | |
| FVC (L) | Mean | 3.20 | 2.78 | 4.85 | 3.41 |
| Median (IQR) | 2.65 (2.03) | 2.51 (1.45) | 4.56 (1.33) | 3.22 (1.06) | |
| FVC (% predicted NHANES III) | Mean | 76 | 88 | 98 | 99 |
| Median (IQR) | 72 (20) | 85 (19) | 98 (18) | 99 (18) | |
| FVC (% predicted GLI) | Mean | 102 | 103 | 99 | 99 |
| Median (IQR) | 104 | 104 | 99 | 99 | |
| IQR | 18 | 17 | 18 | 19 | |
| FEV1/FVC | Mean | 0.84 | 0.87 | 0.76 | 0.79 |
| Median (IQR) | 0.86 (0.09) | 0.88 (0.08) | 0.78 (0.12) | 0.81 (0.10) | |
| FEV1/FVC (% predicted NHANES III) | Mean | 98 | 98 | 96 | 96 |
| Median (IQR) | 98 (11) | 98 (10) | 97 (13) | 98 (11) | |
| FEV1/FVC (% predicted GLI) | Mean | 96 | 96 | 94 | 95 |
| Median (IQR) | 98 (11) | 98 (9) | 97 (13) | 97 (11) | |
| FEF25–75 (L/s) | Mean | 2.88 | 2.79 | 3.32 | 2.64 |
| Median (IQR) | 2.39 (1.83) | 2.47 (1.55) | 3.13 (2.13) | 2.58 (1.60) | |
| FEF25–75 (% predicted NHANES III) | Mean | 94 | 97 | 87 | 88 |
| Median (IQR) | 89 (38) | 92 (41) | 83 (45) | 87 (42) | |
| FEF25–75 (% predicted GLI) | Mean | 93 | 93 | 87 | 90 |
| Median (IQR) | 95 (37) | 94 (35) | 88 (47) | 92 (44) | |
| Number of spirometry maneuvers (SPAMANU) | Mean | 4 | 3 | 3 | 3 |
| Median (IQR) | 3 (3) | 3 (3) | 3 (2) | 3 (2) | |
| Number of data points in raw curve (SPXPTS) | Mean | 622 | 593 | 1099 | 935 |
| Median (IQR) | 648 (450) | 605 (475) | 1063 (518) | 908 | |
| AEX-FV (ATPS, L2/s) | Mean | 1.24 | 1.09 | 6.31 | 3.81 |
| Median (IQR) | 0.91 (1.65) | 0.74 (1.62) | 4.01 (6.26) | 2.50 (2.75) | |
| AEX-FV (BTPS, L2/s) | Mean | 1.46 | 1.27 | 7.40 | 4.46 |
| Median (IQR) | 1.06 (1.94) | 0.87 (1.90) | 4.68 (7.34) | 2.93 (3.22) | |
| Best AEX-FV (BTPS, L2/s) | Mean | 2.79 | 2.29 | 11.35 | 7.03 |
| Median (IQR) | 2.26 (2.00) | 2.09 (1.69) | 8.36 (11.17) | 4.93 (5.04) | |
AEX-FV, area under the expiratory flow-volume; ATPS, ambient temperature and pressure saturated; BTPS, body temperature ambient pressure saturated; FEV, forced expiratory volume; FVC, forced vital capacity; GLI, Global Lung Initiative; NHANES, National Health and Nutrition Examination Survey.