Table 1 Characteristics of the primary studies included in the meta-analysis
From: A systematic review and meta-analysis on tubal ligation and breast cancer risk
First author | Year | Study design | Country | Population | Quality Score* | TES | ES | LL | UL | Adjusted for: |
|---|---|---|---|---|---|---|---|---|---|---|
Brinton L et al. | 2000 | Case Control | USA | Women 20–44 years | High | OR | 1.09 | 0.9 | 1.3 | Race, age at first birth, number of births, and years of education |
Braga C et al. | 1996 | Case Control | Italy | Women 23–74 years | High | OR | 0.6 | 0.3 | 1.3 | Age, center, education, parity, age at first birth, menopausal status/age at menopause, age at menarche, history of benign breast disease, family history of breast cancer, and use of oral contraceptives |
Press DJ et al. | 2011 | Case Control | USA | Women 35–64 years | High | OR | 0.93 | 0.84 | 1.03 | Age, race, study site, age at menarche, first-degree family history of breast cancer, number of term pregnancies, educational status, and duration of hormone therapy use |
Dorjgochoo T et al. | 2009 | Cohort | China | Women 40–70 years | High | RR | 1.22 | 0.95 | 1.55 | |
Eliassen AH et al. | 2006 | Cohort | USA | Women 30–55 years | High | RR | 0.95 | 0.88 | 1.03 | Multivariate-adjusted relative risk for time in 2-year periods, age in months, age at menarche, parity, age at first birth, height, weight change since age 18, body mass index at age 18, first-degree family history of breast cancer, benign breast disease, alcohol consumption, physical activity, oral contraceptive use, menopausal status and type of menopause, and use of postmenopausal hormones |
Gaitskell K et al. | 2016 | Cohort | UK | Women 50–64 years | High | RR | 0.99 | 0.97 | 1.01 | Age, region, socioeconomic status, parity, age at first birth, hysterectomy, smoking, alcohol intake, physical activity, body mass index, and use of the oral contraceptive pill or menopausal hormones |
Gaudet MM et al. | 2013 | Cohort | USA | Women 50–74 years | High | RR | 1.06 | 0.69 | 1.18 | |
Shin MH et al. | 1996 | Case Control | Korea | OR | 0.37 | 0.19 | 0.68 | |||
Irwin KL et al. | 1988 | Case Control | USA | Women 20–54 years | High | OR | 1.2 | 1.0 | 1.3 | Age, data collection center, parity, menopausal status, family history of breast cancer, and history of benign breast disease |
Iversen L et al. | 2007 | Cohort | UK | Women who were using oral contraceptives | High | RR | 1.21 | 0.70 | 2.10 | |
Nichols H et al. | 2013 | Cohort | USA | Women 35–74 years | High | RR | 0.91 | 0.82 | 1.02 |