Resource allocation is of increasing concern as we seek to provide necessary services to our citizens within the confines of balanced budgets. Of particular interest to those allocating resources is the issue of efficiency or cost effectiveness (cost/those who benefit). Although budgetary constraints tend to focus attention on cost effectiveness, consideration of program effectiveness (the number of people who actually benefit/those who theoretically could benefit), itself, must be a primary concern of medical research and practice. Without this information, we cannot be assured that our patients are receiving the best care possible, let alone secure funding for programs that promise the best return for each dollar spent.