I need help with my survival analysis.

See this article for help setting up and analyzing Kaplan-Meier survival curves using Prism 5.

Step-by-step instructions for Prism 3 or Prism 4 are included in our library of Step-by-Step Examples. Also check the following answers to specific problems:

• I did a survival analysis, but the graph doesn't look right. Most of my subjects were censored, but the graph line falls to near zero.
• Why does Prism tell me that median survival is undefined? Can I still believe the P value telling me that the two groups are significantly different?
• I'm doing survival analysis on several treatment groups. When I select all the groups for comparison, the results are not significant. But when I select two groups, I sometimes get a significant result, sometimes not, depending on which two I select. Is this correct?