In Matrix you have a list of risks and each of those is voted against a set of criteria/assessments. You can have up to 9 assessments set up and you can select which of those to include when you run your voting process.
To choose which assessments to run:
In Matrix go to Edit > Preferences and click on the Assessments tab.
Ensure that only the assessments that you wish to include are ticked.
Additional assessments can be selected and run after your first session of voting. For example you may wish to vote on inherent scores only and view the results on a heatmap prior to enabling the residual votes. To do this simply return to the Preferences menu and select the new items.