. Author manuscript; available in PMC: 2024 Jan 9.

Published in final edited form as: J Radiol Prot. 2014 Apr 14;34(2):363–388. doi: 10.1088/0952-4746/34/2/363

Table 1.

An example of the procedure to merge different scanner model groups from different data sources for CT scanners manufactured by GE.

ImPACT		CT-Expo		NEXT		Break Down					Final Database
Model Group	CTDI¹	Model Group	CTDI	Model Group	CTDI	Model	CTDI				Model Group	CTDI
Model Group	CTDI¹	Model Group	CTDI	Model Group	CTDI	Model	ImPACT	CT-Expo	NEXT	Average
FX/i, LX/i	18.9	DX/i, FX/i, LX/i, ZX/i	15.2	FX/i, LX/i	20.9	FX/i	18.9	15.2	20.9	18.3	FX/i, LX/i	18.3
ZX/i, NX/i	14.7	NX/i, -Pro	15.2	DX/i	13.2	LX/i	18.9	15.2	20.9	18.3	ZX/i, NX/i	14.9
						ZX/i	14.7	15.2		14.9	DX/i	14.2
						NX/i	14.7	15.2		14.9	-Pro	15.2
						DX/i		15.2	13.2	14.2
						-Pro		15.2		15.2

Normalized CTDIw only for head phantom and the tube potential of 120 kVp was included for illustrative purpose.