Table 3.

Hazard ratios comparing 5-year breast cancer-specific survival of women with interval cancers with women with screen-detected cancers, only including nondense breasts versus only including dense breasts

	All			Nondense breasts			Dense breasts			P value for interaction terma
	HR	95% CI	P value	HR	95% CI	P value	HR	95% CI	P value
Model 1b	3.50	2.25 to 5.44	<0.001	3.62	2.17 to 6.06	<0.001	3.00	1.26 to 7.17	0.013	0.742
Main model (model 2)c	2.17	1.36 to 3.47	0.001	2.43	1.44 to 4.10	0.001	1.41	0.53 to 3.74	0.486	0.304
Model 3d	1.69	1.03 to 2.76	0.038	1.76	1.01 to 3.09	0.047	1.26	0.47 to 3.38	0.649	0.337

^aTest of interaction between density and mode of detection (screen-detected cancer vs interval cancer). CI, confidence interval; HR, hazard ratio.

^bAdjusted for age, body mass index (BMI) and hormone replacement therapy (HRT) use.

^cAdjusted for age, BMI, HRT use and tumor size.

^dAdjusted for age, BMI, HRT use, tumor size and lymph node metastasis.