Category Systematic Error (Σ), in mm Random Error (σ), in mm
Mediolateral (ML) Craniocaudal (CC) Anterioposterior (AP) Mediolateral (ML) Craniocaudal (CC) Anterioposterior (AP)
Population 3.5 3.8 2.8 2.3 2.5 2.1
BB 2.7 2.3 2.1 3.8 4.3 3.5
VC 2.1 2.6 2.5 3.3 4.1 4.5
Table 3: Systematic (Σ) and random (σ) errors calculated for population, VC and BB groups.