Perhaps the best way to characterize "outcomes research" is it seeks to determine how the patient can be made better overall, not just have the disease treated, even with the current accepted treatment of choice. This challenges both the science and the compassionate art of medicine, health care systems, and individuals. Outcomes research includes record-based research and patient-based research. The field uses some particular methodologies, but a primary distinction of outcomes research is a focus on patient-based outcomes assessment, such as quality of life, functional status, utility, and satisfaction. The classical prospective observational outcomes study should be designed to test a hypothesis and often uses, but is not limited to, a cohort study design with assessment of multiple variables and comparison of outcomes using statistical adjustment. Although results from an observational study design must be interpreted with caution, given the potential for underlying bias and confounding, nevertheless, in some cases, these studies can yield useful results that assist in clinical management.