Table 4.
Linear regression models exploring the interaction of joint bleeding and A1M as explanatory factors for oxidative damage in the joint in all 122 subjects.
| Explanatory factors | Dependent factor: log10 sf-Carbonyl |
|||||||
|---|---|---|---|---|---|---|---|---|
| aEffect, unstandardized (95%CI) | bStandardized effect | p-Value | Adjusted R2 for model | Partial correlation | Collinearity statistics, cVIF | |||
| Model 1 Heme and A1M | Block 1 | log10 sf-Heme | 0.288 (0.088, 0.488) | 0.277 | 0.005 | 0.094 | 0.263 | 1.2 |
| sf-A1M | -0.034 (-0.058, -0.010) | -0.267 | 0.005 | -0.263 | 1.1 | |||
| Block 2 | log10 ratio sf-A1M/sf-Heme | -1.549 (-0.392, -2.706) | -1.522 | 0.009 | 0.141 | -0.246 | 44.1 | |
| Model 2 Hb and A1M | Block 1 | log10 sf-Hb | 0.094 (0.011, 0.178) | 0.210 | 0.027 | 0.065 | 0.205 | 1.1 |
| sf-A1M | -0.028 (-0.050, -0.005) | -0.220 | 0.016 | -0.222 | 1.0 | |||
| Block 2 | log10 ratio sf-A1M/sf-Hb | -1.386 (-0.272, -2.500) | -3.106 | 0.015 | 0.104 | -0.225 | 212.7 | |
Age, sex, and diagnosis were included as confounders in all models with Heme as proxy for bleeding in model 1 and Hb in model 2. In both models age, gender, diagnosis, sf-A1M and log10 sf-Heme or log10 sf-Hb was entered in the first block, with the interaction variable log10 ratio sf-A1M/sf-Heme or log10 ratio sf-A1M/sf-Hb entered together with the other variables in block 2.
aEffect (regression coefficient) the estimate in average change in the dependent factor log10 sf-Carbonyl that corresponds to a 1-unit change in the explanatory factors in the models.
bStandardized effect: the estimate in average change in the dependent factor log10 sf-Carbonyl expressed in standard deviations that corresponds to a 1 standard deviation change in the explanatory factors in the models.
cVIF (variance inflation factor): VIF higher than 10 indicates multicollinearity between variables.