From: Value of serum and induced sputum surfactant protein-D in chronic obstructive pulmonary disease
Multiple linear regression model for six month exacerbation frequency by serum and induced sputum SP-D levels | ||||
Coefficient B | Standard error | t | p | |
Constant | −0.37 | 0.32 | −1.15 | 0.25 |
Serum SP-D levels | 0.008 | 0.002 | 4.22 | 0.0001 |
Sputum SP-D levels | 0.011 | 0.009 | 1.18 | 0.247 |
Multiple linear regression model for induced sputum SP-D levels by six month exacerbation frequency and number of years on inhaled steroid treatment. | ||||
Coefficient B | Standard Error | t | p | |
Constant | 16.948 | 3.78 | 4.4 | 0.0001 |
Six month exacerbation frequency | 1.38 | 2.14 | 0.64 | 0.525 |
Number of years on inhaled steroid treatment | 2.848 | 0.53 | 5.37 | 0.0001 |
Multiple linear regression model for serum SP-D levels by age, FEV1 (%) and six month exacerbation frequency | ||||
Coefficient B | Standard error | t | p | |
Constant | 17.660 | 70.64 | 0.25 | 0.80 |
Age | 1.461 | 1.08 | 1.35 | 0.187 |
FEV1(%) | −0.61 | 0.45 | −1.36 | 0.182 |
Six month exacerbation frequency | 42.598 | 9.85 | 4.32 | 0.0001 |