Table 2 Propensity score matching before and after data using demographic (sex, age, height, smoking status, and pack-years) information for non-dust-exposed subjects and dust-exposed subjects
From: Quantitative CT-based structural alterations of segmental airways in cement dust-exposed subjects
| Â | Before propensity score matching | After propensity score matching (1:4) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
NDE subjects | DE subjects | St.Diff. | NDE subjects | DE subjects | St.Diff. | |||||
(N = 255) | (N = 63) | (N = 164) | (N = 41) | |||||||
N | (%) | N | (%) | N | (%) | N | (%) | |||
Sex | ||||||||||
 Male | 99 | (38.8) | 45 | (68.2) | 61.6 | 80 | (48.8) | 20 | (48.8) | 0.0 |
 Female | 156 | (61.2) | 21 | (31.8) |  | 84 | (51.2) | 21 | (51.2) |  |
Age | ||||||||||
 mean ± std | 51.0 | ±15.1 | 70.5 | ±7.5 | ±1.6 | 49.7 | ±15.4 | 70.0 | ±8.0 | ±1.7 |
Height | ||||||||||
 mean ± std | 161.4 | ±9.6 | 159.9 | ±10.1 | ±0.2 | 162.9 | ±9.7 | 157.9 | ±11.3 | ±0.5 |
Smoking | ||||||||||
 Non/Former Smoking Participants | 224 | (87.8) | 57 | (86.4) | 4.4 | 144 | (87.8) | 36 | (87.8) | 0.0 |
 Current Smoking Participants | 31 | (12.2) | 9 | (13.6) |  | 20 | (12.2) | 5 | (12.2) |  |
Pack-years | ||||||||||
 mean ± std | 4.6 | ±13.2 | 14.7 | ±21.9 | ±0.6 | 4.4 | ±12.3 | 10.4 | ±22.7 | ±0.3 |
BMI | ||||||||||
 mean ± std | – | – | – | 24.4 | ±3.3 | 24.1 | ±2.8 | 0.372* | ||