Table 4.

Association of Percent Density with Risk of Breast Cancer for the BI-RADS, CM and ABDM Method^* Contralateral Side^↑,^‡

BI-RADS					CM (PD)				ABDM (PDA)
Category	Case/ Control	OR (95%)	AUC	View	Quartile PD or PDA§,‖	Case/ Control	OR (95%)	AUC	Case/ Control	OR (95%)	AUC
1	92/254	1.00 (reference)	0.61	CC	1	56/175	1.00 (reference)	0.63	41/178	1.00 (reference)	0.64
2	43/78	1.58 (1.01–2.48)			2	87/176	1.69 (1.13–2.53)		81/172	2.31 (1.47–3.64)
3	86/182	1.49 (1.04–2.14)			3	90/176	2.10 (1.37–3.22)		100/178	3.02 (1.94–4.70)
4	148/198	2.61 (1.82–3.75)			4	130/176	3.81 (2.42–5.99)		141/175	5.18 (3.26–8.20)
					Continuous**		1.67 (1.42–1.97)	0.64		1.79 (1.53–2.10)	0.64
				MLO	1	57/175	1.00 (reference)	0.60	36/175	1.00 (reference)	0.64
					2	98/178	1.83 (1.23–2.74)		75/179	2.53 (1.56–4.10)
					3	96/175	2.00 (1.32–3.05)		114/179	4.48 (2.76–7.27)
					4	113/179	2.82 (1.81–4.40)		139/174	6.14 (3.74–10.08)
					Continuous**		1.56 (1.33–1.83)	0.63		1.89 (1.61–2.23)	0.64

^*All models were adjusted for age and body mass index.

^↑For all models, p-values from tests for trend were < 0.001.

^‡Numbers of cases and controls are the same for analyses of PD and PD_A performed within CC (363 cases, 703 controls) and MLO (364 cases, 707 controls) views. Numbers of cases and controls for BI-RADS analyses were 369 cases and 712 controls.

^§Cutpoints for quartiles of CM percent density (PD) for craniocaudal (CC) view are 15.8, 25.8, 35.6 and for mediolateral oblique (MLO) view are 14.5, 23.7, 32.7.

^‖Cutpoints for quartiles for ABDM percent density (PD_A) for CC view are 15.4, 20.1, 23.9 and for MLO view are 15.7, 19.4, 23.0.

^**Continuous PD and PD_A assessments correspond to a one standard deviation increase. SDs are 14.6 and 13.5 for PD from CC and MLO views and 5.5 and 5.1 for PD_A from CC and MLOs.