Journal of Clinical Epidemiology 54 (2001) 93–98 0895-4356/01/$ – see front matter © 2001 Elsevier Science Inc. All rights reserved. PII: S0895-4356(00)00263-8 The Cooperative Familial Registry for Breast Cancer Studies: design and first year recruitment rates in Ontario Heather J. Sutherland a, *, Jeanie Lacroix b , Julia Knight b , Irene L. Andrulis c , Norman F. Boyd d , the Ontario Cancer Genetics Network e a The Ontario Familial Breast Cancer Registry, 610 University Avenue, Toronto, Ontario M5G 2M9, Canada b Cancer Care Ontario, Toronto, Ontario, Canada c Ontario Cancer Genetics Network and Lunenfeld Institute, Mount Sinai Hospital, Toronto, Ontario, Canada d Epidemiology, Statistics and Behavioral Research, Ontario Cancer Institute, Toronto, Ontario, Canada e Ontario Cancer Genetics Network, Cancer Care Ontario, Toronto, Ontario, Canada Received 7 January 2000; received in revised form 4 April 2000; accepted 17 April 2000 Abstract The Ontario Familial Breast Cancer Registry (OFBCR) is one of six international sites of the Cooperative Familial Registry for Breast Cancer Studies collecting family history, epidemiologic information, and blood samples from families (with various patterns of familial risk) for the purpose of studying the etiology of breast cancer. To invite 2361 female breast cancer patients residing in Ontario to take part in the Registry, a package was sent that included a Family History Questionnaire. Several variations of mailing and follow-up strategies were employed. Overall, the response rate was 67%. The best response (74%) was achieved by following up our introductory package of information with a postcard 10 days later and a telephone call several weeks thereafter. Given the design of the project, which involves a considerable commitment on the part of both patients and their family members, we are impressed by the positive response of these women. © 2001 Elsevier Science Inc. All rights reserved. Keywords: Familial breast cancer; Recruitment methods 1. Introduction Family studies of breast cancer have shown that there is an inherited component to the etiology of the disease and have led to the discovery of genes that are associated with a strik- ing increase in risk [1,2]. These studies have been carried out mainly in highly selected families with several members af- fected by the disease, and not identified as a result of any de- fined sampling strategy. To generate unbiased estimates of the risks of disease associated with these genes, and of their interaction with other risk factors, we need to study families selected from the population in a systematic manner. Further, to ensure that the families selected are representative of the population from which they were selected we must achieve a high response rate from those approached. To promote interdisciplinary studies in the etiology of breast cancer, and to foster translational research in this area, the National Institutes of Health issued a Request for Applications (RFA) in 1994 to establish a Cooperative Fa- milial Registry for Breast Cancer Studies (CFRBCS). The purpose of the Registry was to collect pedigree information, epidemiological data, and biological specimens from sub- jects with a family history of breast cancer, and to identify a population at high risk for breast cancer that will participate in the evaluation of new preventive and therapeutic strate- gies. The CFRBCS comprises six sites, four in the United States, one in Australia, and one in Canada (Ontario). Three sites utilize high-risk cancer genetics clinics for recruitment and three are population-based registries. The consortium will undertake cooperative studies using pooled data. In this article we describe the development and first-year recruitment experience of one of the population-based sites, the Ontario Familial Breast Cancer Registry. Specifically, this report describes the effect of different mailing and fol- low-up strategies on response rates to a questionnaire used to identify patterns of cancer in families of patients with newly diagnosed breast cancer. Only the experience with fe- male participants is reported here as males were targeted for another provincial study during the first year of recruitment for the Registry. The Registry is still accruing subjects (year * Corresponding author. Tel.: (416) 946-4409; fax: (416) 946-4410. E-mail address: hsutherl@oci.utoronto.ca