"A matched comparison group is a subsample of participants selected to be a point of comparison for a group receiving an intervention. Participants for the matched comparison group are selected based on having similar characteristics to the group receiving the intervention."
Hanita, M., Ansel, D., Shakman, K. (2017). Matched-comparison group design: An evaluation brief for educational stakeholders [White paper]. Teacher and School Leader Incentive Program. https://www.edc.org/sites/default/files/uploads/matched_comparison_group_design.pdf