ArticleBreast cancer research : BCR1999
The Million Women Study: design and characteristics of the study population. The Million Women Study Collaborative Group.
Article in Breast cancer research : BCR, 1999. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 58 papers, 3 of them syntheses that pooled it.
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Who cites it
58 citing papers in PubMed, 3 syntheses or guidelines pooled it, 119 citations in OpenAlex.
- Night Shift Work and Breast Cancer Incidence: Three Prospective Studies and Meta-analysis of Published Studies.Journal of the National Cancer Institute · 2016Pooled it
- Reproductive factors and specific histological types of breast cancer: prospective study and meta-analysis.British journal of cancer · 2009Pooled it
- Alcohol, tobacco and breast cancer--collaborative reanalysis of individual data from 53 epidemiological studies, including 58,515 women with breast cancer and 95,067 women without the disease.British journal of cancer · 2002Pooled it
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- Trial
- The effect of menopause and hysterectomy on systemic vascular endothelial growth factor in women undergoing surgery for breast cancer.BMC cancer · 2008Trial
- Risk factors for multimorbidity of cardiovascular diseases in the prospective Million Women Study.Open heart · 2026Article
- Can I Do Better Than AI: A Comparative Analysis of a Medical Student Essay Created With and Without Generative AI.Cureus · 2026Article
- Inequalities in all-cause mortality by ethnicity in the United Kingdom: a systematic review and meta-analysis.The Lancet regional health. Europe · 2025Article
- Diet-wide analyses for risk of colorectal cancer: prospective study of 12,251 incident cases among 542,778 women in the UK.Nature communications · 2025Article
- Implications of hormonal carcinogenesis for transgender and gender-diverse people undergoing gender-affirming hormone therapy: an up-to-date review.BMJ oncology · 2024Review
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- The evolutionary ecology of age at natural menopause: implications for public health.Evolutionary human sciences · 2020Article
- Validation of the Oxford WebQ Online 24-Hour Dietary Questionnaire Using Biomarkers.American journal of epidemiology · 2019Article
- Body mass index and use and costs of primary care services among women aged 55-79 years in England: a cohort and linked data study.International journal of obesity (2005) · 2019Article
- Association of ten gastrointestinal and other medical conditions with positivity to faecal occult blood testing in routine screening: a large prospective study of women in England.International journal of epidemiology · 2019Article
- Cohort Profile: the Million Women Study.International journal of epidemiology · 2019Article
- Big data: Some statistical issues.Statistics & probability letters · 2018Article
- Histological subtypes of ovarian cancer associated with parity and breastfeeding in the prospective Million Women Study.International journal of cancer · 2018Article
- Antidepressants, Depression, and Venous Thromboembolism Risk: Large Prospective Study of UK Women.Journal of the American Heart Association · 2017Article
Corrections and comments
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1 author.
Funding
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Abstract
objectivesTo describe the design of the Million Women Study and the characteristics of the study population. STUDY
designPopulation-based cohort study of women aged 50-64 in the UK.
settingWomen are asked to join the Million Women Study when they are invited to routine screening for breast cancer at 61 of the screening centres of the UK National Health Service Breast Screening Programme (NHSBSP). An estimated 71% of women screened by the NHSBSP return a completed questionnaire.
participants800 000 women were recruited between May 1996 and June 1999, and it is planned that an additional 200 000 will be recruited by the year 2000.
resultsThe characteristics of the first 121 000 women recruited into the Million Women Study are described here. At recruitment 33% of the study population were currently using hormone replacement therapy and 47% had used it at some time. Over half (54%) had used oral contraceptives, and 18% were current smokers at the time of recruitment. Before they were screened 1.4% of the women had been diagnosed with breast cancer in the past, 6% had a mother with a history of breast cancer and 3.7% had a sister with a history of breast cancer. It is estimated that 1 million women will have been recruited by early in the year 2000, and that by the end of the year 2002 there will be 5000 screen-detected breast cancers and 23 000 deaths in the cohort, the majority of which will be attributed to cancer (12 600 deaths) and circulatory disease (8000 deaths).
conclusionsBy the end of the year 2002, the Million Women Study will have sufficient statistical power to detect relative risks of 0.8 or less, or of 1.2 or more in current users compared with never users of hormone replacement therapy for mortality from breast cancer, colorectal cancer, lung and ovarian cancer, ischaemic heart disease and stroke.
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