ANY-maze Help > The ANY-maze reference > The Protocol page > The elements of a protocol > Additional information > Treatment groups > Choosing how ANY-maze should assign animals to treatment groups

Choosing how ANY-maze should assign animals to treatment groups

In brief

ANY-maze generally expects animals to be divided into distinct groups which it calls treatment groups, because this is the most common situation. You can change this so that the system doesn't use treatment groups, but assuming you are using them, then there's a question of how the animals should be assigned to the groups.

For example, imagine you have 20 animals in 4 groups; the system could put the first 5 animals in the first group, the next 5 in the second, etc. or it could put the first animal in the first group, the second animal in the second group, etc. There are, of course, other possibilities too.

The options in the Treatment group settings allow you to choose exactly how this assignment is performed. It's important to understand that the animals will always* be tested in order, in other words animal 1 will be tested first, then animal 2, then animal 3 etc.

* The test order may differ if animals will be tested more than once, i.e. in multiple trials (see Specifying the order in which animals will be tested) and can also be changed at the time tests are performed.

Details

There are four options for assigning animals to treatment groups. They are:

Manual assignment

This option will prevent ANY-maze from assigning the animals to any treatment groups (they'll all be recorded as Unassigned); instead, you will need to specify the group for each animal individually which you can do using the

View animals option on the Experiment page. This option is useful when none of the others meet your needs.

This option may be disabled in 'Ugo Basile Operon' protocol mode, if the protocol has been set to automatically randomise the allocation of animals between treatment groups. This choice will have been made when adding an Operon to the protocol.

Block assignment

Assigning animals in blocks will assign the first 'n' animals to the first treatment group, the next 'n' animals to the second group etc., where 'n' is the size of the group. For example, if you have 4 groups (A, B, C and D) each consisting of 5 animals then block assignment would place the first 5 animals in group A, the next 5 in group B, etc., i.e. A A A A A B B B B B C C C C C D D D D D.

Cyclic assignment

Assigning animals in a cyclic fashion will assign the first animal to the first treatment group, the second animal to the second group etc. until each group includes one animal. It would then cycle back to the start again. For example, if you have 4 groups (A, B, C and D) each consisting of 5 animals then cyclic assignment would place the first animal in group A, the next in group B, the next in group C, etc., i.e. A B C D A B C D A B C D A B C D A B C D.

Random assignment

Assigning animals in a random fashion will, not surprisingly, simply assign the animals to the treatment groups in a random order. For example, if you have 4 groups (A, B, C and D) each consisting of 5 animals then the system might place the first animal in group C, the second in group A etc., e.g. C A D C B D A A B D C B A D C B C D A B.

You can change the assignment system you wish to use at any time, although it will only affect new animals added to the experiment, it won't change the assignment of any existing animals. Nevertheless, you can always change the assignment of an animal using either the Animal details report or the View animals option on the Experiment page.

ANY-maze help topic T0585