THE ROLE OF COMMUNITY-BASED LONGITUDINAL-STUDIES IN EVALUATING TREATMENT EFFECTS - EXAMPLE - BENIGN PROSTATIC HYPERPLASIA

To determine the appropriateness and effectiveness of medical interven tions, it is necessary to understand both the natural history of the c onditions the interventions are intended to treat or prevent, and the normal reference ranges of tests used in diagnosis and management. The acquisition of this information through clinic-based studies can yiel d misleading conclusions owing to selection bias. What appears to be i ntervention-related variation in outcomes may be variation in the magn itude and form of selection bias. To minimize selection bias, populati on-based studies are required. Results from the Olmsted County Study o f Urinary Symptoms and Health Status Among Men were used to show how a population-based longitudinal study of the natural history of benign prostatic hyperplasia (BPH) can complement research programs of the BP H Patient Outcomes Research Team. Population-based studies of disease natural history are a necessary part of medical outcomes research, and deserve greater emphasis in the medical treatment effectiveness resea rch initiative of the Agency for Health Care Policy and Research.