Deleting response sets will move the references to the unreviewed state at a specific Level, depending on which response sets are deleted. Deleting response sets can be useful if you want to re-review the reference from scratch.
To delete the response set submitted by yourself or another user, a Datarama report can be generated including the references which you'd like to delete response sets for. This can also be done via the Reference Status Report (in the Reports menu). Clicking a number in the report will auto-generate a Datarama report including those references (e.g. clicking 100 included references will create a Datarama report with those 100 includes).
At the bottom of the Datarama report, click Delete # Response Sets to clear the response sets from the references in the report. After doing so, you will be directed to reconcile your references - reconciling will "update" your Project and move references back to the "Unreviewed" state at the lowest Level you deleted response sets for.
Example: References are fully reviewed at Level 3 - if you would like to move them to the unreviewed state at Level 2, you would generate a Datarama report including the data from both Levels 2 and 3 (select these Levels in the Data to Display section of Datarama Report Settings). Once the response sets are deleted at these Levels, the references will be "Unreviewed" at Level 2.