Table 1.

For Breast Cancer, Approximate OPERA Scores for Some Established Risk Factors in Western Countries^a

Risk Factor	OPERA	Comment
Sex	10
Age	?	Depends on age range and distribution
All familial causes	3	Known and unknown factors
Mammographic density	1.4	Likely to increase with new measures
Known polygenic markers	1.6	Likely to increase with new studies
Known gene mutations	1.2–1.7	Depends on age at diagnosis and ethnicity
Family history	1.2	First-degree only; yes/no
No. of childbirths	1.1	Greater for countries with more births

Abbreviation: OPERA, odds per adjusted standard deviation.

^a This paper is illustrative and about a (new) concept; the table is intended as a description of general results when applying the concept to breast cancer.