Authors' disclosures of potential conflicts of interest are found at the end of this article. S tudies of how patients respond to treatment over time are fundamentally important to understanding how therapies influence quality of life and progression of disease during survi-vorship. When investigators examine change over time in continuous variables (e.g., patient self-reports of pain, fatigue,...

The branch of statistics relative to analysis of predictable period of time until one or more event occurs is termed survival analysis. Survival analysis is a system of data collection and analysis where the outcome variable is the time until the event of an interest occurs [1]. The technique deals with the creation of timing data that goes with event of either failure or death. However the pat...