Familial risks of breast and prostate cancers: Does the definition of the at risk period matter?
Aim: 'Being at familial risk' may have different connotations in studies on familial risk of cancer. The register-based definition of a family history considers individuals with an affected relative at familial risk independently of the family member's diagnostic time. Alternatively, the individuals are classified to be at familial risk only after the diagnosis date of their relative, relevant to