An assessment of existing models for individualized breast cancer risk estimation in a screening program in Spain

Table 1 Characteristics of the study sample

		No cancer⁽¹⁾(N = 13380)		Cancer (N = 329)		Total (N = 13709)
		N	%	N	%	N	%	p-value⁽³⁾
Age at first mammogram, y	50-54	4975	37.18	120	36.47	5095	37.17	0.026
	55-59	3602	26.92	110	33.43	3712	27.08
	60-64	4216	31.51	83	25.23	4299	31.36
	65-69	587	4.39	16	4.86	603	4.40
Age at menarche, y	<12	2493	18.63	62	18.84	2555	18.64	0.990
	12-13	5243	39.19	129	39.21	5372	39.19
	> = 14	5505	41.14	134	40.73	5639	41.13
	Unknown	139	1.04	4	1.22	143	1.04
Age at first live birth, y	<20	1065	7.96	26	7.90	1091	7.96	0.050
	20-24	6242	46.65	151	45.90	6393	46.63
	25-29	4109	30.71	91	27.66	4200	30.64
	>29	966	7.22	37	11.25	1003	7.32
	No children	902	6.74	23	6.99	925	6.75
	Unknown	96	0.72	1	0.30	97	0.71
Body mass index	<25	3347	25.01	92	27.96	3439	25.09	0.569
	25-29	4519	33.77	105	31.91	4624	33.73
	30-34	1944	14.53	53	16.11	1997	14.57
	> = 35	675	5.04	16	4.86	691	5.04
	Unknown	2895	21.64	63	19.15	2958	21.58
Breast density (BI-RADS)⁽²⁾	1	2969	22.19	50	15.20	3019	22.03	<0.001
	2	5378	40.19	102	31.00	5480	39.98
	3	2338	17.47	83	25.23	2421	17.65
	4	2067	15.45	73	22.19	2140	15.63
	Unknown	628	4.69	21	6.38	649	4.73
No. of biopsies	0	13263	99.13	325	98.78	13588	99.12	0.513
No. of biopsies	> = 1	117	0.87	4	1.22	121	0.88
Menopausal status	No	747	5.58	18	5.47	765	5.58	0.930
Menopausal status	Yes	12633	94.42	311	94.53	12944	94.42
Affected first-degree relatives	No	12647	94.52	302	91.79	12949	94.46	0.195
	Yes	704	5.26	26	7.90	730	5.32
	Unknown	29	0.22	1	0.30	30	0.22
Previous benign breast disease	No	12420	92.83	292	88.75	12712	92.73	0.005
	Yes	960	7.17	37	11.25	997	7.27

⁽¹⁾Ductal carcinoma in situ cases were included as no cancer cases.
⁽²⁾1: Almost entirely fat, 2: Scattered fibroglandular densities, 3: Heterogeneously dense, 4: Extremely dense.
⁽³⁾P-values have been obtained excluding the unknown values.