| Forced entry model | Backward elimination model | ||||
---|---|---|---|---|---|---|
β ± SD | p value | VIF | β ± SD | p value | VIF | |
PANSS score | ||||||
 Sex | −0.13 ± 0.22 | 0.57 | 2.42 |  |  |  |
 Age | −0.62 ± 0.32 | 0.06 | 5.04 | −0.54 ± 0.15 | <0.001 | 1.16 |
 Smoking status | −0.15 ± 0.20 | 0.44 | 1.91 |  |  |  |
 Duration of illness | 0.16 ± 0.25 | 0.53 | 3.22 |  |  |  |
 CP equivalent dose | 0.11 ± 0.18 | 0.52 | 1.38 |  |  |  |
 Vitamin B12 | 0.05 ± 0.15 | 0.76 | 1.31 |  |  |  |
 Folate | 0.30 ± 0.19 | 0.12 | 1.73 | 0.35 ± 0.16 | 0.04 | 1.41 |
 Homocysteine | 0.38 ± 0.21 | 0.09 | 2.31 | 0.27 ± 0.16 | 0.10 | 1.43 |
 l-serine | 0.00 ± 0.00 | 1.00 | 3.26 |  |  |  |
 d-serine | 0.43 ± 0.25 | 0.10 | 3.08 | 0.38 ± 0.14 | 0.01 | 1.07 |
 Glycine | −0.13 ± 0.20 | 0.53 | 2.13 |  |  |  |
 Methionine | 0.34 ± 0.16 | 0.05 | 1.35 | 0.29 ± 0.15 | 0.07 | 1.29 |
 Genotype131 | −0.29 ± 0.20 | 0.16 | 1.96 | −0.25 ± 0.15 | 0.10 | 1.18 |
 Genotype133 | −0.14 ± 0.23 | 0.55 | 2.61 |  |  |  |
Positive PANSS score | ||||||
 Sex | −0.03 ± 0.21 | 0.89 | 2.42 | −0.71 ± 0.19 | <0.001 | 2.21 |
 Age | −0.68 ± 0.30 | 0.04 | 5.04 |  |  |  |
 Smoking status | −0.04 ± 0.18 | 0.82 | 1.91 |  |  |  |
 Duration of illness | 0.25 ± 0.24 | 0.32 | 3.22 | 0.31 ± 0.19 | 0.11 | 2.07 |
 CP equivalent dose | 0.12 ± 0.12 | 0.45 | 1.38 |  |  |  |
 Vitamin B12 | 0.14 ± 0.16 | 0.38 | 1.31 |  |  |  |
 Folate | 0.32 ± 0.18 | 0.08 | 1.73 | 0.25 ± 0.14 | 0.08 | 1.12 |
 Homocysteine | 0.31 ± 0.20 | 0.15 | 2.31 |  |  |  |
 l-serine | 0.07 ± 0.24 | 0.77 | 3.26 |  |  |  |
 d-serine | 0.22 ± 0.24 | 0.36 | 3.08 |  |  |  |
 Glycine | 0.31 ± 0.20 | 0.13 | 2.13 | 0.47 ± 0.13 | <0.001 | 1.06 |
 Methionine | 0.26 ± 0.16 | 0.11 | 1.35 | 0.19 ± 0.15 | 0.20 | 1.25 |
 Genotype131 | −0.32 ± 0.19 | 0.11 | 1.96 | −0.23 ± 0.14 | 0.11 | 1.16 |
 Genotype133 | −0.06 ± 0.22 | 0.78 | 2.61 |  |  |  |
Negative PANSS score | ||||||
 Sex | −0.05 ± 0.23 | 0.82 | 2.42 |  |  |  |
 Age | −0.42 ± 0.34 | 0.23 | 5.04 | −0.25 ± 0.15 | 0.11 | 1.07 |
 Smoking status | −0.18 ± 0.21 | 0.38 | 1.91 | −0.27 ± 0.16 | 0.11 | 1.27 |
 Duration of illness | 0.15 ± 0.27 | 0.58 | 3.22 |  |  |  |
 CP equivalent dose | 0.12 ± 0.24 | 0.50 | 1.38 |  |  |  |
 Vitamin B12 | 0.05 ± 0.18 | 0.79 | 1.31 |  |  |  |
 Folate | 0.14 ± 0.20 | 0.49 | 1.73 |  |  |  |
 Homocysteine | 0.37 ± 0.23 | 0.12 | 2.31 | 0.24 ± 0.18 | 0.19 | 1.48 |
 l-serine | 0.14 ± 0.27 | 0.61 | 3.26 |  |  |  |
 d-serine | 0.30 ± 0.26 | 0.27 | 3.08 | 0.47 ± 0.19 | 0.02 | 1.73 |
 Glycine | −0.53 ± 0.22 | 0.02 | 2.13 | −0.61 ± 0.20 | 0.004 | 1.76 |
 Methionine | 0.28 ± 0.17 | 0.12 | 1.35 |  |  |  |
 Genotype131 | −0.37 ± 0.21 | 0.09 | 1.96 | −0.16 ± 0.15 | 0.30 | 1.10 |
 Genotype133 | −0.31 ± 0.24 | 0.22 | 2.61 |  |  |  |