I'm trying to make Kaplan-Meier survival curves for a couple of groups of dogs with heart disease. Most of the curves are fine, but one starts at about 0.75 rather than 1.0. It then behaves correctly. The data I'm using is
Where 1.00 indicates still alive, 2.00 indicates the dog has died. I've tried altering the values, it still does the same. I'm using SPSS 15.0. Any ideas?
Thanks for trying, but the scale isn't the problem. 1 is displayed on the axis, but the curve is only plotted from 0.75 onwards. It should start at 1 because all the animals were alive when the study started.