. Author manuscript; available in PMC: 2016 Sep 1.

Published in final edited form as: Toxicol Appl Pharmacol. 2015 Jun 3;287(2):149–160. doi: 10.1016/j.taap.2015.05.019

Table 3.

Influence of Cyp1b1 genotype on tumor incidence and multiplicity.

Treatment	Genotype	Tumor Incidence^a			Tumor Multiplicity
Treatment	Genotype	%^b	p-value^c	Ratio^d	Mean±SE^e	p-value^f	Ratio^g
BaP	Cyp1b1^+/+	88.89	1	1.172	3.88±0.67	0.495	0.682
	Cyp1b1^−/−	87.50	1	1.172	4.89±0.77	0.495	0.682
CTE	Cyp1b1^+/+	86.21	1	1.017	3.96±0.62	0.983	0.837
	Cyp1b1^−/−	76.47	1	1.017	3.73±0.45	0.983	0.837
DBC	Cyp1b1^+/+	100.00	7.409 × 10⁻³	2.627	7.82±1.00	0.029	1.950
	Cyp1b1^−/−	72.73	7.409 × 10⁻³	2.627	3.29±0.41	0.029	1.950

Tumor incidence evaluated by cumulative tumor incidence function to account for early non-cancer related mortalities

Percent tumor incidence at 20 weeks for each condition

Statistical difference in tumor incidence between WT and null animals for each treatment group calculated by Gray’s log rank test for equality adjusted for FDR (Gray 1988)

Hazards ratio calculated for WT compared to null in each treatment group based on the proportional hazards model for the subdistribution of developing a tumor

Tumor multiplicity calculated as the mean number of tumors per tumor-bearing animal (±SE)

Statistical difference in tumor multiplicity between WT and null animals for each treatment group calculated using a generalized linear model to account for cage and cohort effects

Estimated ratio of mean tumor multiplicity for WT compared to null