Table 5.
Linear regression analysis of different particle measures based on stationary area measurements as dependent and personal inhalable cobalt exposure as independent variablesa,b
| Aerosol fraction (Dependent; Independent) | Regression | Prediction | |||
|---|---|---|---|---|---|
| β (p) | 95% CI (β) | r 2 | Predicted concentrationc | 95% CI (y)d | |
|
Inhalable Co (S);
Inhalable Co (P) |
0.884 (<0.001) |
0.626–1.14 | 0.675 | 0.00530 | 0.000611–0.0460 |
|
Particle surface area (S);
Inhalable Co (P); |
−0.153 (0.127) |
−0.353 to 0.048 | 0.118 | 3.49 | 1.00–12.3 |
|
Particle number (S);
Inhalable Co (P) |
0.015 (0.799) |
−0.104 to 0.134 | 0.003 | 2540 | 944–6900 |
P, personal exposure measurements; β, regression coefficient; 95% CI (β), 95% confidence interval for β; r 2, correlation coefficient; S, stationary measurements.
aAll data ln-transformed, except predicted concentrations presented in original units.
b n = 28, except for particle surface area (n = 22) and particle number (n = 27).
cPredicted concentration = predicted individual concentration for inhalable cobalt 0.02mg m−3.
dCI (y) = 95% confidence interval for predicted dependent metrics, individual concentrations.