====== Is there a way to send invitation emails only to specific participants? ======

  * In fact, it is very desirable that you send the invitations mainly to people who match your inclusion criteria. 
  * To do this, select "Assign participants" in your experiment. 
  * Before displaying all participants, you can select filter criteria via "+ Add condition", e.g. a specific entry in the "Gender" field. 
  * Subsequently, only participants that match these criteria will be displayed via "Search and display".