Check occurences of how many times a value repeat itself between sheets.

Hello everyone,

I've got one problem. I created a challenge using forms. And a linked spreadsheets which contains the emails used on this prize drawn.

I need to use a formula that checks between 4 different sheets. Being more specific I need to create a process to check if each user has completed this 4 reviews.

I'm looking for a formula that will help me to find this information without having to compare and count each list.

Does anyone have any idea what should I do?


Many thanks guys.