How can I avoid underestimating risks?

Ideally, the input pedigree should be complete, up-to-date and free of errors. However, we recognise that in practice, it is often very difficult to collect family history data, and that no pedigree is ever truly complete.

Errors and omissions in the input pedigree data can lead to a misspecification of risk, and so the user should consider these data carefully. The following actions will help to prevent this from happening:

1. All individuals with cancer must be recorded with an age at diagnosis, an age at last follow up and a year of birth. If any of these parameters are missing, they should be estimated. 

2. The year of birth and age at last follow up should be supplied for all family members, or as many as possible.

3. If a family member has had a prophylactic mastectomy or oophorectomy, it is advisable to set her age at last follow up as her age at the time of the operation assuming she has subsequently remained free of cancer. These procedures are known to reduce the risk of developing breast cancer or ovarian cancer.

4. Genetic test results must be included.

5. Family members of Ashkenazi Jewish origin must be recorded