Table 1.

Summary characteristics of the 19 DENSNP studies

BC casesNoncasesOverall
CharacteristicCategoryNo. of studiesN (%)N (%)N (%)
Overall195,110 (30)11,785 (70)16,895 (100)
Study designCohort316 (0.3)1,582 (13)1,598 (9)
Cross-sectional538 (1)3,064 (26)3,102 (18)
Case–control53,280 (64)2,217 (19)5,497 (33)
Nested case–control31,599 (31)2,099 (18)3,698 (22)
Family-based3177 (3)2,823 (24)3,000 (18)
Source of demographic and reproductive dataIn-person interview61,631 (32)1,276 (11)2,907 (17)
Postal questionnaire123,378 (66)8,831 (75)12,209 (72)
Telephone interview1101 (2)1,678 (14)1,779 (11)
Age,a y<409221 (4)145 (1)366 (2)
40–4917937 (18)1,857 (16)2,794 (17)
50–59181,643 (32)4,843 (41)6,486 (38)
60–69161,659 (32)4,011 (34)5,670 (34)
≥7013650 (13)929 (8)1,579 (9)
ParityaNulliparous19614 (12)1,167 (10)1,781 (11)
Parous194,329 (85)10,479 (89)14,808 (88)
Unknown8167 (3)139 (1)306 (2)
Menopausal statusaPremenopausal161,185 (23)2,241 (19)3,426 (20)
Perimenopausal513 (0.2)251 (2)264 (2)
Postmenopausal183,769 (74)9,195 (78)12,694 (77)
Unknown6143 (3)98 (1)241 (1)
PMH use (at age ≥55)Ever161,703 (53)3,364 (46)5,067 (48)
Never161,326 (41)3,474 (47)4,800 (45)
Unknown8178 (6)537 (7)715 (7)
Source of anthropometric dataSelf-reported93,784 (74)5,909 (50)9,693 (57)
Measurements by trained staff101,326 (26)5,876 (50)7,202 (43)
BMI,a kg/m2<25192,284 (45)5,071 (43)7,355 (44)
≥ 25192,737 (54)6,597 (56)9,334 (55)
Unknown1089 (2)117 (1)206 (1)
Average time interval between mammography and data collection (months),b≤682,129 (42)4,330 (37)6,459 (38)
>6112,981 (58)7,455 (63)10,436 (62)
Mammographic side, viewL–CC8831 (16)2,547 (22)3,378 (20)
R–CC6949 (19)1,830 (16)2,779 (16)
LR average–CC32,402 (47)2,285 (19)4,687 (28)
L–MLO3465 (9)1,978 (17)2,443 (14)
R–MLO1447 (9)418 (4)865 (5)
LR average–MLO416 (0.3)2,727 (23)2,743 (16)
Density reading softwareCumulus153,814 (75)10,213 (87)14,027 (83)
Madena41,296 (25)1,572 (13)2,868 (17)

Abbreviations: BC, breast cancer; CC, craniocaudal; L, left; MLO, mediolateral oblique; R, right.

  • aAt time of mammography and/or data collection.

  • bAverage time interval for each study given in Supplementary Table S2 (range, 0–5 years).