Characteristics associated with participation at various stages at the Ontario site of the cooperative family registry for breast cancer studies.

PURPOSE: The Ontario site of the Cooperative Family Registry for Breast Cancer Studies collects cancer family history, other risk factor information, and biospecimens from individuals with incident breast cancer and their relatives within a defined population. Sampling is based on age and defined genetic risk criteria. The purpose of this analysis was to evaluate the representativeness of the respondents.
METHODS: We examined characteristics associated with response to requests for information, biospecimens, and permission to contact relatives among those diagnosed with breast cancer in 1996 in the province of Ontario.
RESULTS: Overall, response was good among the largest group, white women, and did not differ between those with and without a family history of breast and/or ovarian cancer. Women who described themselves as other than white and men tended to have lower response. Women of Ashkenazi heritage had high response except for permission to contact relatives.
CONCLUSIONS: There was no evidence that participation in a familial breast cancer registry derived from a population-based cancer registry was influenced by having a family history of breast or ovarian cancer. The use of a cancer registry approach is likely more representative of the population than clinic-based recruitment of families for genetic studies.