## Validation of PhEq_bootstrap [Software]

Hi Helmut!

» Now for the bad news. There is one thing stupid in the software when it comes to validation (line 535 of the source Conv_to_learn1.pas):

RandSeed:=random(random(1000000))+random(random(1000000));

That means that the seed of the (pseudo)random number generator is always a random number itself. Therefore, it is impossible to reproduce runs. Try it: you will not get exactly my results.

What a coincidence! I was in a meeting recently with a regulatory agency and the issue of reproducibility came up since the agency couldn't reproduce the bootstrap f2 values we reported in the dossier. My first thought was the different seed number. I opened the source files one by one and searched words like random, seed, to get the line.

» IMHO, that’s bad coding practice.

Indeed. End user should be able to specify the seed number to be able to reproduce the analysis. I always leave a variable for seed number in my SAS code for bootstrap of BE data.

All the best,
Shuanghe