Table 1 Basic characteristics of 10 studies
Study | Source of study subjects | Age (years) | Source of receptor information (percentage of subjects with the information) | Number of subjects | Adjustment for potential confounders in data analyses | ||
|---|---|---|---|---|---|---|---|
Cases | Controls | ER+PR+/ER-PR- cases | Controls | ||||
Cohort studies | |||||||
[9] | Iowa Women's Health Study, USA (7 years' follow-up, 1986–1992, 241,627 person-years) | 55–69 at baseline | Medical record (65%) | 414/80 | - | BMI, BMI at age 18 years, WHR, age at menarche, type of MP, age at MP, oophorectomy history, FHBC, parity, age at first live birth, contraceptive, non-contraceptive estrogen use, ALC | |
[10] | Nurses' Health Study Cohort, USA (20 years' follow-up, 1980–2000, 1,029,414 person-years) | 30–55 at baseline in 1976 | Medical record (74%) | 1,281/417 | - | Age, age at menarche, time since menopause, parity at age, age at birth, FHBC, HBBD, years on ET, years on EPT, BMI, height, ALC | |
Population-based case-control studies | |||||||
[11] | North Carolina, USA | DMV/HCFA | 20–74 | Majority from medical record (91%) | 381/262 | 790 | Age at menarche, nulliparity/age at first full-term pregnancy, breastfeeding, abortion or miscarriage, BMI, WHR, OC, HT, FHBC, medical radiation to the chest, SMK, ALC, education, age, race |
[12] | Georgia, Washington, and New Jersey, USA | RDD | 20–44 | Medical record (78%) | 616/360 | 1,397 | Age, race, education, BMI, WHR, parity, age at first birth, breastfeeding, OC, SMK, ALC, recreational exercise at age 12–13 and 1 year prior to interview, age at menarche, FHBC, MP, geographic site |
[13] | Ontario, Canada | Assessment roll of the Ministry of Finance | 25–74 | Hospital laboratories and medical record (87%) | 1,901/737 | 3,691 | Age, age at menarche, parity, age at first live birth, OC, BMI, ALC, SMK, breastfeeding, HBBD, FHBC, current strenuous activity for pre-MP women; age at MP, HT, and oophorectomy history for post-MP women |
[14] | Victoria and New South Wales, Australia | Electoral roll | <40 | Medical record (81%) | 323/181 | 564 | Age, study center, study period, education, country of birth, marital status, FHBC, BMI, age at menarche, number of live births, OC |
[7] | Georgia, Washington, Michigan, Pennsylvania, and California, USA | RDD | 35–64 | Medical record (82%) | 2,130/1081 | 4,668 | Age, race, education, FHBC, age at menarche, study site, number of full-term pregnancies and age at first full-term pregnancy only for models of parous women |
[8] | California, USA | Neighbours | 20–49 | Medical record (84%) | 854/385 | 440 | Age, race, education, FHBC, age at menarche, gravidity, number of full-term pregnancies, OC, BMI, ALC, MP and HT, age at first full-term pregnancy and breastfeeding only for parous women |
Hospital-based case-control studies | |||||||
[15] | Aichi Cancer Hospital, Nagoya, Japan | Hospital | ≥25 | Not specified (40%) | 176/141 | 21,714 | Age, occupation, FHBC, age at menarche, menstrual regularity as a teenager, age at MP, age at first full-term pregnancy, number of full-term pregnancies, breastfeeding, ALC, SMK |
[16] | Yale, New Haven Hospital, USA | Hospital | 40–80 | Single laboratory (76%) | 104/107 | 401 | Age, race, FHBC, age at menarche, nulliparity/age at first full-term pregnancy, breastfeeding, MP, BMI, ever estrogen use, ALC, SMK |