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Kaplan-Meier and Nelson-Aalen

R

rajiv_p_lk_2001

Member
Can someone please confirm if I have got the right idea of these two methods of calculating survival functions.

The only difference in the calculation is that in Nelson-Aalen we calulate the cumulative hazard function by addition hazard rates. And in Kaplan-Meier we multiply the survival rates to calculate the survival function.

If I am wrong can you please explain the difference.

Thanks
 
You are right. To be specific, you take 1 less the product of the survival probabilities for Kaplan-Meier.

If you use the approximation of exp(x) = 1+x, you can show that F<KM> is equal to the F<NA>.

Have fun!
 
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