Please be advised that if you are running a custom task program in 3.8.x or 3.9.x that there is a randomization bug in the Block Table if square brackets are used in the TP List (i.e. TP List in the Block Table = 10-15, [1, 2, 3]) and List Reps or Block Reps are > 1. Round brackets in the TP List are not affected by this issue. If List Reps and Block Reps are 1 then there is no problem.

Any TPs listed inside square brackets will always be randomized to the same order for a given block. The randomized order will be different each time the task is run.

While the bug will be fixed in an upcoming release, we wanted to provide immediate notice to all potential users as the bug is difficult to detect.

To workaround the bug, manually repeat the TP List as many times as required.

If you need to randomize TP List = 5, [1,2,3], List Reps = 2, Block Reps = 2 then instead use:

TP List = [5, [1,2,3]], [5, [1,2,3]], [5, [1,2,3]], [5, [1,2,3]], List Reps = 1, Block Reps = 1

Our thanks to the lab in Calgary who spotted the bug and reported it to us.