ASCERTAINMENT CORRECTED RATES - APPLICATIONS OF CAPTURE-RECAPTURE METHODS

Accurate rates, though fundamental to epidemiology, are often very dif ficult to obtain. Incidence, prevalence, and mortality rates have trad itionally been established through either passive reporting surveillan ce systems, through active surveillance systems, or by a combination o f the two methods. Typically, when researchers employ these approaches they do not formally evaluate or correct for the degree of underascer tainment. Undercount of cases is a potent determinant of rates which w e cannot continue to ignore. We believe all rates should be adjusted f or underascertainment in order to achieve a truer picture of the risk and risk factors of disease. Here, we present a procedure to ascertain ment correct rates based upon well established capture-recapture metho ds.