Comparative effectiveness research: moving medical oncology forward.

Comparative effectiveness research (CER) is critically needed in medical oncology to improve the care being delivered to oncology patients. As medical oncologists are forced to rely on insufficient data as a part of daily treatment decision making, and as the cancer treatment landscape evolves quickly relative to other areas of medicine, CER is particularly pressing in our field. Continued reliance on randomized clinical trials is a part of the solution, but it cannot be the sole answer. As new and richer data sources become available addressing quality of life, resource utilization, and other critical elements, the implementation of CER will advance. Its true power will lie in linkages to "learning health systems" and real-time application to the day-to-day practice of medicine.