Table 2.
Bivariate analysis of numerical variables and localization errors a
| Variable | Median (IQR) | EPLE | TPLE | ||
|---|---|---|---|---|---|
| Test | P | Test | P | ||
| Age (years) | 30 (20–40) | −0.027 | 0.423 | 0.045 | 0.187 |
| Skin-skull distance (mm) | 6.4 (5.1–8.1) | 0.161 | <0.001 b | 0.258 | <0.001 b |
| Skull thickness (mm) | 6.7 (4.9–8.7) | 0.079 | 0.020 b | 0.170 | <0.001 b |
| Acute skull angle (degrees) | 76.1 (66.5–84.2) | −0.273 | <0.001 b | −0.262 | <0.001 b |
| Intracranial length (mm) | 41.0 (30.7–55.5) | - | - | 0.079 | 0.020 b |
aEPLE, entry point localization error; TPLE, target point localization error. None of the values are normally distributed (Shapiro-Wilk normality test p-values are < 0.001 for all variables). Bivariate analysis (Spearman correlation) was performed. The relationship between EPLE and intracranial electrode length is not relevant
bSignificant