. Author manuscript; available in PMC: 2018 Feb 20.

Published in final edited form as: Chem Res Toxicol. 2016 Dec 21;30(2):540–551. doi: 10.1021/acs.chemrestox.6b00268

Table 4.

Percent difference (%DIFF) of predicted TSNAs and total TSNA amounts derived from measured individual TSNA quantities

	Tobacco Filler			ISO smoking regimen			CI Smoking regimen

TSNA	R²	DIFF (%)	95% Confidence Limits of DIFF (%)	R²	DIFF (%)	95% Confidence Limits of DIFF (%)	R²	DIFF (%)	95% Confidence limits of DIFF (%)

NNK	0.56	−2.6	−24 to 19	0.82	4.2	−24.6 to 33	0.64	4.6	−15.9 to 25
NAB	0.85	−0.2	−10.2 to 10	0.93	7.4	−14.8 to 29.5	0.93	3.5	−8.9 to 15.8
NAT	0.61	−0.6	−9.8 to 8.6	0.96	−0.3	−16.3 to 15.6	0.92	1.9	−11.9 to 15.7
NNN	0.89	0.2	−11 to 11.4	0.95	4.3	−7.9 to 16.6	0.98	2.7	−7.2 to 12.5

ISO, International Organization of Standards machine-smoking regimen; CI, Health Canada Intense machine-smoking regimen; R², Coefficient of Determination; DIFF (%) = [(sum of measured quantities of all four TSNAs –Predicted Total TSNAs)/ sum of measured quantities of all four TSNAs] x 100.