You have included this variable category in two contradictory ways in this experiment

This variable category node has been used in two contradictory ways in your diagram. The diagram currently suggests that this variable category is both distributed evenly between the groups shown on the diagram and that this variable category is allocated to specific groups.

This variable category node is connected to an independent variable of interest node which is connected to the allocation node using ‘categories allocated separately’. This means all variable categories connected to this independent variable of interest node will be distributed evenly between the groups directly following the allocation (e.g. if the variable category nodes are ‘male’ and ‘female’ all groups will have both sexes and have the same number of each sex).

You have also put the variable category nodes on either group or intervention nodes in the diagram. This means that you want this variable category to only be in the group(s) (or following intervention nodes) labelled with this variable category node.

See below for different options for your diagram depending on your experiment.

If the independent variable of interest is an animal characteristic (e.g. sex or strain) and you want all variable categories distributed evenly between the groups shown on your diagram

If you want the categories of the independent variable of interest to be distributed evenly between the groups shown on your diagram (e.g. you want each group to have the same proportion of male and female animals in them), leave the independent variable of interest node connected to both the allocation node and the analysis nodes. The variable category nodes from this independent variable of interest should only be connected to the independent variable of interest, delete any that are tagged to group or intervention nodes (see images below).

This approach is only appropriate for animal characteristics (e.g. sex, strain or age).

The above experiment should be represented like this:

If the independent variable of interest is an intervention and you will allocate different variable categories to different groups shown on your diagram (e.g. a drug treatment and a vehicle)

If you want each category of the independent variable of interest to be allocated to a different group on your diagram, delete the link connecting the independent variable of interest node to the allocation node. Leave the independent variable of interest node connected to the analysis node and make sure the variable category nodes are on intervention nodes (not on group nodes). You may need to add more group and intervention nodes to accurately represent your experiment (see images below). 

This is appropriate for interventions that can be allocated to animals such as a drug treatment, or a surgical intervention.

The experiment above should be represented like this:

This issue may cause other prompts to be triggered inappropriately, please disregard other warnings. Once you have modified the diagram, please critique it again.