Relative survival is a net survival measure representing cancer survival in the absence of other causes of death. Relative survival is defined as the ratio of the proportion of observed survivors in a cohort of cancer patients to the proportion of expected survivors in a comparable set of cancer free individuals. The formulation is based on the assumption of independent competing causes of death. The relative survival adjusts for the general survival of the U.S. population for that race, sex, age, and date at which the age was coded. If age, race, sex, or year information is missing, that individual is excluded from the analysis. When calculating relative survival, an Expected Survival Table must be chosen.
By selecting Relative Survival from the Cancer Survival Measures on the Statistic tab, the following statistics will be shown for each survival interval in the output life tables.
- Number of cases entering the interval alive
- Number of cases dying, lost to follow up, or withdrawn alive* during the interval
- The adjusted number of alive* cases for each interval
- Observed survival, expected survival, and relative survival for the interval
- Cumulative observed, expected, and relative survival
- Standard errors for the interval observed survival, cumulative observed survival, interval relative survival, and cumulative relative survival
* These statistics do not appear in the results matrix unless selected from the matrix options.