Table 1. Correlation analysis ( $\phi$ & P-value are correlation score and p-value) between the absolute and relative volume difference of all cartilage samples with the difference of their absorption coefficient and a reference absorption coefficient. Scenarios: A) Air as surrounding medium and microCT-estimated surface diameter, B) air as surrounding medium and drill-bit surface diameter, C) water as surrounding medium and microCT-estimated surface diameter, and d) water as surrounding medium and drill-bit surface diameter.

Scenarios	Absolute volume difference		Relative volume difference
	Correlation parameters		Correlation parameters
	$\phi$	P-value	$\phi$	P-value
A	-0.1249	0.419	-0.0424	0.419
B	-0.0845	0.5852	0.0499	0.5852
C	-0.1924	0.4162	-0.1067	0.4162
D	0.3684	0.11	0.4045	0.11