WAERS: Estimation of the Relative Survival

This tool provides automatic calculation of Observed and Relative Survival. Relative Survival (RS) can be interpreted as the proportion of alive patients after T years of follow-up in the hypothetical situation that cancer is the only possible cause of death. The tool returns a table and two different types of graphs.
The table contains the number of individuals at risk, the follow up (in years), the Observed and Relative Survival and its confidence intervals for the overall individuals and also stratified by the strata columns defined in the data file.
The first graph describes the observed survival, the expected survival and its confidence intervals along the follow up. Each figure represents a category from the strata variables.
The second graph shows the relative survival and its confidence intervals. A figure per each strata variable is shown.
The age group and sex specific mortality rates available for the calculation of relative survival for each reference population is specified in the drop down country selector.

Methodology (PDF)

Files must be ASCII type, ";" separated and unquoted values (i.e: ".txt" or ".csv" files).

Data file (click here to view an example):
a) followUp: Time of follow-up for each individual expressed in years
b) status: 0 = alive; 1= dead
c) age: Age fot each individual at the beggining of the study
d) sex:1= male; 2= female
e) yearInit: calendar year for each individual at the beginning of the study

If the user wants to make an statistical analysis according to stratification variables, he can add more optional columns in the data file (see below). User must add as many columns as stratification variables wants to include in the analysis. The name of each stratification variable is specified by the user.

f) Strata: one or more columns depending of the number of the stratification variables. In each column the user must define the stratification variable categories.

Note: Regardless of the mandatory sex column to perform the analysis was included in the data file, if you want to have the analysis stratified by sex it is necessary to enter another column with the sex description. Confidence value (1-α): The confidence value to calculate the confidence interval of observed and relative survival. It has to be between 0 and 1 (usually 0.95). 

Mortality only is available for some countries of Europe, Asia, Oceania and America (you can check the countries included in the methodology document).

NOTE: This process could take some minutes!!

Mortality of the reference population (Country):

Warning: file size must be less than 10MB.

Name of the file:

Confidence value:


Clèries R, Ribes J, Gàlvez J, Melià A, Moreno V, Bosch F.X. Automatic calculation of relative survival through the web. The WAERS project of the Catalan Institute of Oncology. Gac Sanit 2005;19:71-75

Cleries,R.; Valls,J.; Esteban,L.; Galvez,J.; Pareja,L.; Sanz,X.; Alliste,L.; Martinez,J.M.; Moreno,V.; Bosch,X.; Borras,J.M.; Ribes,J.M. WAERS: an application for Web-assisted estimation of relative survival. Med Inform Internet Med 2007; 32(3):169-175.

Mortality and population are obtined from: