Median survival time
The time from either diagnosis or treatment at which half of the patients with a given disease are found to be, or expected to be, still alive. In a clinical trial, median survival time is one way to measure how effective a treatment is.
Also called median overall survival and median survival.
Reference: National Cancer Institute (NCI). Dictonary of cancer terms. Internet. Accessed January 26, 2011. Available at http://www.cancer.gov/dictionary/?expand=M.