Normality assessment of caudate nucleus (CN) morphometric data. Kernel density plots for normalized measurements with corresponding Shapiro–Wilk p-values showing significant deviation from normality for all parameters (p<0.05), justifying non-parametric statistical analysis. Right length (yellow dashed), right width (brown dash-dot), left length (red dotted), and left width (magenta solid) are visualized with corresponding Shapiro–Wilk p-values: right length: p=0.001, right width: p=0.021, left length: p<0.001, and left width: p=0.003. All tests indicate significant deviation from normality, validating the use of non-parametric methods for further analysis.