Table 11.

Comparison between organ dose obtained in this study and organ dose predicted by published exponential relationships relating organ dose with patient diameter/perimeter.

	Male			Female
	Normal	Obese class I	Obese class II	Normal	Obese class I	Obese class III
Chest CT
Average chest diameter (cm)	26.8	32.3	34.5	27.8	30.5	35.1
Lung dose simulated in this study (mGy/100 mAs)	8.73	7.14	5.72	9.63	6.10	4.68
Lung dose predicted using the equation of Li et al. (mGy/100 mAs)1	9.49	7.83	7.25	9.18	8.35	7.12
Discrepancy	9%	10%	27%	−5%	37%	52%
Abdominal CT
Average abdominal diameter (cm)	25.2	32.0	35.4	27.0	30.0	35.7
Stomach dose estimated in this study (mGy/100 mAs)	8.53	6.74	5.21	8.77	5.41	4.01
Stomach dose predicted using the equation of Turner et al. (mGy/100 mAs)2	9.29	7.29	6.47	8.72	7.83	6.40
Discrepancy	9%	8%	24%	−1%	45%	59%

¹The equation for lung dose and the set of scan parameters in this study is H_lung = exp (− 0.035d_chest + 3.19) in mGy/100 mAs. See supplementary materials of Li et al. (Ref. ⁷).

²The equation for stomach dose is $H_{\mathrm{stomach}}=3.780\times \exp (-0.0113\times \pi d_{\mathrm{abomen}-\mathrm{pelvis}})\times {\mathrm{CTDI}}_{\mathrm{vol}}.$ The CTDI_vol for the set of scan parameters in this study was 6.01 mGy/100 mAs. See Turner et al. (Ref. ¹⁰).