Types of Cancer Research. Cancer research includes four broad categories. Basic research seeks to understand the fundamental aspects of nature. It provides the foundation for advances against cancer. Clinical research tests drugs, medical devices, or other interventions in human volunteers to improve all aspects of patient care. Population-based research explores the causes of cancer, cancer trends, and factors that affect the delivery and outcomes of cancer care in specific populations. Translational research moves basic research findings into the clinic and clinical research findings into everyday care. In turn, results from clinical and population-based studies can guide basic research.