Table 4. Average control mean Gray value at 70 kVp and slope of the trend in control mean at 70 kVp, under the conditions “with” and “without metal” and “with” and “without MAR”.

		Control mean at 70 kVp	Slope at 70 kVp
Metal	MAR	Mean ± SE	Slope ± SE
Without	Without	49.4 ± 0.3	−0.56 ± 0.01
	With	38.3 ± 0.3a	−0.20 ± 0.01a
With	Without	49.5 ± 0.3b	−0.57 ± 0.01b
	With	38.2 ± 0.3a,c	−0.21 ± 0.01a,c

MAR, metal artefact reduction; SE, standard error.

^aSignificantly (p ≤ 0.05) different from without metal and without MAR.

^bSignificantly (p ≤ 0.05) different from without metal and with MAR.

^cSignificantly (p ≤ 0.05) different from with metal and without MAR.