Multivariate linear regression models for cognitive symptom severity in patients with PD as assessed by MMSE scores
| Independent variables | Coefficient | SE | r | t | p Value |
| Constant | 39.526 | ||||
| Disease duration (years) | 0.0612 | 0.095 | 0.097 | 0.650 | 0.519 |
| Age (years) | −0.223 | 0.056 | −0.512 | −4.003 | <0.001** |
| Gender (male) | 0.208 | 1.422 | 0.022 | 0.147 | 0.884 |
| Plasma α-synuclein level | −0.226 | 0.096 | −0.331 | −2.351 | 0.023* |
In this model, the MMSE score of patients with PD was set as the dependent variable, with age, gender, disease duration and plasma level of α-synuclein set as independent variables. r: correlation coefficient based on the model of multiple linear regression; t: t value for the coefficient of each parameter in the model; p: for r or t; R2-adjusted=0.3004, p<0.001 for the model. *: statistically significant, p<0.05; **: p<0.01.
MMSE, Mini-Mental State Examination; PD, Parkinson's disease.