Table 2.

Correlation between NNAL levels and other measures of SHS exposure (n = 72)

Measure	Urine NNAL	Urine NNAL-to-creatinine ratio	Urine cotinine	Urine hydroxycotinine	Nicotine badge	Self-reported SHS exposurea
Urine NNAL		.97, p < .0001	.75, p < .0001	.74, p < .0001	.33, p = .004	.34, p = .003
Urine NNAL-to-creatinine ratio			.71, p < .0001	.67, p < .0001	.31, p = .008	.29, p = .01
Urine cotinine				.73, p < .0001	.36, p = .002	.29, p = .01
Urine hydroxycotinine					.43, p < .0001	.25, p = .03
Nicotine badge						.10, p = .37

Note. NNAL = 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol; SHS = secondhand smoke. Spearman’s rank-order correlation and p values.

^aSelf-reported total hours of exposure during the past 7 days.