I have a question about the calculation of the overall survival rate for both control and treatment group. Suppose the one-year progression-free survival rate of the control group is 60% and that of the treatment group is 80%. Is the overall one-year progression-free survival rate for both groups 70% (suppose the ratio of subject numbers between control and treatment is 1:1)?

Would you please give me some idea on how to calculate the overall survival rate (or maybe more accurately, the overall proportion) for both arms in a trial?

Thank you.

Best regards,

Alex