About helenjad

helenjad · ‎06-15-2023

For anyone who are interested in the case, the weight computation is matched when adding 0.5 to each cell not 0.5/n_hi.

helenjad · ‎06-10-2023

In a follow-up, I have run below cases. The two cases give the same estimate: data test1; input strat trt $ responder $ count; datalines; 1 Test Responder 4 1 Test NR 8 1 Pbo Responder 2 1 Pbo NR 11 2 Test Responder 0 2 Test NR 12 2 Pbo Responder 0 2 Pbo NR 13 ; run; data test2; input strat trt $ responder $ count; datalines; 1 Test Responder 4 1 Test NR 8 1 Pbo Responder 2 1 Pbo NR 11 2 Test Responder 12 2 Test NR 0 2 Pbo Responder 13 2 Pbo NR 0 ; run; proc freq data=test1; weight count; tables strat*trt * responder/commonriskdiff(column=2 cl=MR correct=NO); run; proc freq data=test2; weight count; tables strat*trt * responder/commonriskdiff(column=2 cl=MR correct=NO); run;

helenjad · ‎06-10-2023

Hello, I've asked when there is a case of double zero event like how to adjust for the zero cell. What if we have a double one case, i.e. both p_h1 and p_h2 are equal to 1, we would also have variance equal to zero. What SAS would do to handle this situation? Below are the reference formula. Thank you!

helenjad · ‎06-06-2023

In a follow-up question similar to the double zero case mentioned above, what if we have a double one case, i.e. both p_h1 and p_h2 are equal to 1, we would also have variance equal to zero. What SAS would do to handle this situation? Thank you.

helenjad · ‎05-22-2023

Thank you! I can match the numbers.

helenjad · ‎05-22-2023

The source document did not have the details if one of the strata is double zero events. If you check the formula, we have If we have double zero events, p_{h1} and p_{h2} are zeros, and V_i^{-1} would be infinity. I'd like to know how it's been handled in SAS since I didn't get error/warning messages.

helenjad · ‎05-19-2023

Hello, I'd like to know more about the details how the MR method is implemented under double zero events. Below is the data and code. data test; input strat trt $ responder $ count; datalines; 1 Test Responder 4 1 Test NR 8 1 Pbo Responder 2 1 Pbo NR 11 2 Test Responder 0 2 Test NR 12 2 Pbo Responder 0 2 Pbo NR 13 ; run; proc freq data=test; weight count; tables strat*trt * responder/commonriskdiff(column=2 cl=MR correct=NO); run; I have tried to do some adjustment for the double zero count like adding 0.5 to the zero cells, adding 1 to the zero cells, adding 0.5 to each cell. It seems the results from SAS output are closest to the one when adding 0.5 to the zero cells. Is this how it's been implemented? Thank you.

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Date Last Visited	‎06-15-2023 03:38 PM

Re: commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double ones

commonriskdiff using MR method in the case of double ones

Re: commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double zero events

commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double ones

commonriskdiff using MR method in the case of double ones

Re: commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double zero events

Re: commonriskdiff using MR method in the case of double zero events

commonriskdiff using MR method in the case of double zero events