42 U.S.C. § 284d — Definitions

(a) Health services research. In this subchapter, "health services research" means research that studies how the way health services are organized, financed, and managed affects the quality, cost, access, and outcomes of care. This term does not cover research on whether a specific service actually works to prevent, diagnose, or treat a medical condition — that's excluded. (b) Clinical research. In this subchapter, "clinical research" means patient-focused research done with human subjects, or research into the causes and effects of disease in groups of people using material that comes from humans (like tissue samples or thinking-related data). To count, a researcher must directly work with human subjects — in an outpatient or inpatient setting — to solve a problem involving human physiology, disease processes, or disease itself. This also covers epidemiological or behavioral studies, research on treatment outcomes, health services research, and the development of new technologies, therapies, or clinical trials.