What data are collected?

The Generations Study involves over 100,000 women, aged 16 years or older resident in the UK. Those taking part in the study were asked to fill out a detailed questionnaire and provide a blood sample. They now complete follow-up questionnaires every few years.


Women taking part in the study have been sent four questionnaires to complete since the start of the study. The questionnaires ask about various factors in a woman's life that might relate to risk of breast cancer – for instance asking about:

  • How many children you have had
  • What age you were at their births
  • Whether and when you have taken the oral contraceptive pill
  • Your weight and physical activity
  • Whether you drink alcohol or smoke
  • Whether you have had breast disease or other medical conditions

The questionnaire information is stored under the custodianship of The Institute of Cancer Research, and the personal information is kept strictly confidential, and seen only by the study team.

Blood samples

Women were also asked to provide a blood sample that will be analysed to obtain information about hormonal, genetic and other factors that might influence the risk of breast cancer.


Every few years after they had joined, participants are invited to fill in follow-up questionnaires to see how the factors the study is investigating change over time, and to enable investigation of how changes in those factors affect breast cancer risk.

Can I take part?

The study has closed recruitment and is now in the stage of following up the women who joined previously.