Depending on the specific requirements for a project, you can create additional fields (columns) for the checklist while:

For example, the Approvers custom field (in the following image) that's added to provide the names of internal and external stakeholder groups who must verify the task output before the Status is set to Done. 

Figure: Tracker checklist in iManage Work (with a custom "Approvers" field)

You also have the flexibility to change the order in which these and the default fields are displayed, and show or hide the fields to suit dynamic project requirements. 

NOTE:

Default fields, can't be deleted. You can only remove them from the table view, but they're always available for selection later. For more information, refer to Changing the fields displayed