I am needing to check for duplicate entries in various worksheets. I don't
want to remove the duplicates, just see if there are any.

i.e. there is a tab created for each week with patients listed. I am
needing to find out if any patients are on more than one sheet. My unique
identifier is the patient id. I know how to create a formula that will find
duplicates from the previous week but what formula can be used to find
duplicates in multiple sheets?

Thanks for any help.

Tami