Public health aspects of breast cancer gene testing in Canada. Part 3: A model of potential need and demand.

Centres offering expert counselling and genetic testing are already experiencing high levels of demand, and yet the potential demand is much greater. There have been few attempts to estimate the potential demand created by particular guidelines for referral or testing. A model of need and demand for genetic services is presented, and research questions are identified that should assist in better prediction of future requirements for genetic counselling and testing. The value of integrated routine data on referral criteria, demand and clinical service load is considerable. Attention needs to be paid to referral at primary care and general specialist levels as well as to expert centres.