Table 4.
Multivariate models building on all significant factors in univariate analysis
| Model | Feature | Unstandardised coefficients (B) | Standard error | Standardised coefficients beta | t | p value |
| 1 | (Constant) | 74.907 | 23.552 | 3.180 | 0.003 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.413 | 0.149 | 0.381 | 2.765 | 0.008 | |
| 2 | (Constant) | 72.028 | 23.730 | 3.035 | 0.004 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.520 | 0.184 | 0.480 | 2.828 | 0.007 | |
| Anti-dsDNA Ab – EliA (IU/ml) | -0.142 | 0.142 | -0.169 | -0.997 | 0.324 | |
| 3 | (Constant) | 68.464 | 26.533 | 2.580 | 0.013 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.512 | 0.187 | 0.472 | 2.732 | 0.009 | |
| Anti-dsDNA Ab – EliA (IU/ml) | -0.137 | 0.145 | -0.163 | -0.947 | 0.349 | |
| Total SLEDAI score | 1.153 | 3.676 | 0.044 | 0.314 | 0.755 | |
| 4 | (Constant) | 63.596 | 31.159 | 2.041 | 0.048 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.506 | 0.190 | 0.467 | 2.658 | 0.011 | |
| Anti-dsDNA Ab – EliA (IU/ml) | -0.132 | 0.147 | -0.158 | -0.901 | 0.373 | |
| Total SLEDAI score | 1.013 | 3.743 | 0.039 | 0.271 | 0.788 | |
| ESR (mm) | 0.208 | 0.677 | 0.044 | 0.307 | 0.761 | |
| 5 | (Constant) | 65.107 | 31.917 | 2.040 | 0.048 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.512 | 0.194 | 0.473 | 2.646 | 0.012 | |
| Anti-dsDNA Ab – EliA (IU/ml) | -0.133 | 0.149 | -0.159 | -0.897 | 0.375 | |
| Total SLEDAI score | 1.137 | 3.808 | 0.044 | 0.299 | 0.767 | |
| ESR (mm) | 2.558 × 10-03 | 0.922 | 0.005 | 0.028 | 0.978 | |
| CRP (mg/l) | 0.154 | 0.522 | 0.057 | 0.295 | 0.769 | |
| 6 | (Constant) | 61.031 | 58.443 | 1.044 | 0.303 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.513 | 0.196 | 0.473 | 2.614 | 0.013 | |
| Anti-dsDNA Ab – EliA (IU/ml) | -0.128 | 0.164 | -0.152 | -0.780 | 0.440 | |
| Total SLEDAI score | 1.196 | 3.919 | 0.046 | 0.305 | 0.762 | |
| ESR (mm) | 8.484 × 10-03 | 0.956 | 0.002 | 0.009 | 0.993 | |
| CRP (mg/l) | 0.144 | 0.541 | 0.053 | 0.267 | 0.791 | |
| Age | 0.108 | 1.284 | 0.015 | 0.084 | 0.934 | |
| 7 | (Constant) | 59.716 | 59.051 | 1.011 | 0.318 | |
| Anti-dsDNA (ELISA) Ab (U/ml) | 0.542 | 0.206 | 0.501 | 2.627 | 0.012 | |
| Anti-DNA-EliA (IU/ml) | -0.134 | 0.166 | -0.160 | -0.808 | 0.424 | |
| Total SLEDAI score | 1.772 | 4.116 | 0.068 | 0.430 | 0.669 | |
| ESR (mm) | -6.240 × 10-03 | 0.965 | -0.001 | -0.006 | 0.995 | |
| CRP (mg/l) | 0.144 | 0.546 | 0.053 | 0.264 | 0.794 | |
| Age | -0.193 | 1.425 | -0.028 | -0.135 | 0.893 | |
| Total SLICC | 5.964 | 11.773 | 0.095 | 0.507 | 0.615 |
Ab, antibody; anti-dsDNA, anti-double-stranded DNA; CRP, C-reactive protein; EliA, fluorescence enzyme immunoassay test for anti-double-stranded DNA (Phadia GmbH); ELISA, enzyme-linked immunosorbent assay; ESR, erythrocyte sedimentation rate; SLEDAI, Systemic Lupus Erythematosus Disease activity index; SLICC, Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index for systemic lupus erythematosus.