Statistical Analysis
Student’s t-test was used to examine the statistical significance of
inter-group (PD vs HCO) differences for values of the PSD-EEG, striatal
[18F]FDOPA PET/CT uptake ratios and cognitive tests parameters. When
comparing PSD-EEG parameters the inter-group comparisons’ p-values were
adjusted according to the Bonferroni correction to avoid the type I
error derived from multiple comparisons. Pearson’s correlation
coefficient (r) or Spearman’s correlation coefficient (ρ - rho) was
calculated to evaluate the associations of the PSD-EEG parameters
revealing statistically significant inter-group differences with the
striatal [18F]FDOPA PET/CT uptake ratios and neuropsychological
parameters. Additionally, to assess the diagnostic accuracy (sensitivity
and specificity) of the PSD-EEG and striatal [18F]FDOPA PET/CT
uptake ratio parameters, the ROC curves were estimated and the area
under the curve (AUC) values were calculated. All statistical analyses
were performed with Statistica version 13.1 software, and the
significance level was set at α = 0.05.