Calculation of survival curves and statistical comparison of two censored populations: a computer program in BASIC

In experimental aging research the handling of censored data imposes a serious problem in the calculation of survival curves of partly censored populations and the statistical comparison of such populations. The presented computer program combines a method to calculate a corrected survival curve and a test to compare two censored populations. In both methods, the proportion of the animals that survive or die during an interval and the number at risk at the start of that interval is used in the calculation of relative survival or death during that interval. The program is written in an elementary BASIC and will run on practically every computer programmable in BASIC. The presented method can be used for testing the difference between survival characteristics of two animal populations but might also be employed in evaluating the effect of a medical treatment.