Table 1. Cohort characteristics by menopausal status, the EPIC study.

	Premenopausal				Postmenopausal
Country	Cohort size (n)a	Baseline age median (range)	Person years	No. of casesb	Cohort size (n)a	Baseline age median (range)	Person years	No. of casesb
Italy, Varese	2411	45 (37–57)	16 783.1	43	2945	58 (41–78)	19 997.2	65
UK	24 515	36 (20–58)	132 210.0	131	16 635	61 (39–80)	89 409.4	264
Cambridge	1510	48 (40–57)	7393.6	15	6243	63 (41–78)	32 679.8	95
Oxford – GPc	1373	45 (36–57)	9125.8	25	2241	57 (40–76)	14 254.3	63
Oxford – HCd	21 632	34 (20–58)	115 690.6	91	8151	60 (39–80)	42 675.3	106
Greece	5107	40 (20–57)	19 042.9	11	4431	61 (40–80)	16 173.7	17
Germany, Potsdam	6320	40 (20–58)	37 057.5	28	5492	59 (39–70)	33 143.1	57
Sweden, Malmo	—	—	—	—	8459	61 (45–74)	62 059.2	194
Denmark	2076	52 (50–58)	13 654.4	51	19 961	58 (50–66)	132 871.6	497
Aarhus	766	51 (50–58)	4920.5	24	5749	58 (50–66)	37 875.9	103
Copenhagen	1310	52 (50–58)	8733.9	27	14 212	58 (50–66)	95 495.7	394
Total	40 429	39 (20–58)	218 747.9	264	57 923	59 (39–80)	354 354.2	1094

^aWomen with complete measured anthropometric characteristics at enrolment and recalled weight at age 20 (German cohort: age 25).

^bInvasive (malignant, primary) breast cancer.

^cGP=general population.

^dHC=health-conscious.