An expected survival table is required in Survival sessions when relative survival statistics or crude probability of death using expected survival are calculated. Together the observed and expected survival are used to generate relative survival.
Each database in SEER*Stat has a default expected survival table. Each year, survival statistics are calculated for the SEER Cancer Statistics Review using the data submission available at the time of publication and that submission's default expected survival table.
The expected survival tables distributed with SEER*Stat contain the expected probabilities of survival generated from U.S. population statistics. Expected survival are obtained from the expected survival table by matching the cohort cases by race, sex, age, and date at which the age was coded.
- The Sex values available in the expected survival table are "Male" and "Female" only.
- The Age values available in the expected survival table are given in single years of age from 0 to 118.
- The Race and Year values available depend on which expected survival table you use.
The available Race values are usually described in the name of the expected survival table.
Year is typically broken out by decennial time period (e.g. 1970, 1980, 1990, 2000). Depending on which survival table is used, not all decennial periods will be present. If a decennial period is not present, SEER*Stat will pick the closest available year. For data year values between decennial periods, the middle year will use the lower decennial survival. Years before the earliest or after the latest decennial period will use the survival of the closest year.
For example, if the "U.S. 1970, 1980, 1990, 2000 (White, Black, Other (AI/API) All races for Other Unspec 1991+ and Unknown)" expected survival table is used:
- Person years less than or equal to 1975 will use the 1970 expected survival.
- Person years between 1976 and 1985 (inclusive) will use the 1980 expected survival.
- Person years between 1986 and 1995 (inclusive) will use the 1990 expected survival.
- Person years greater than or equal to 1996 will use the 2000 expected survival.
It is also possible to prepare your own expected survival tables using SEER*Prep (see Using Your Own Data).