I am trying to establish what should be a simple relationship between two tables. I am a physician, and this DB will hopefully make documenting rounds easier. I believe that I’ve done this sort of relationship before, but it is not working here.

DB #1 Admissions: has information such as the patient’s ID#, the hospital name, hospital number, date of admission etc. There is a calculated field yielding text “true” or “false” if the patient is still in the hospital.

DB #2 Rounds notes. Fields for vitals, objective finding, subjective, etc.

What I would like to do is have in DB2 a drop down menu for patients still in the hospital. I have established a variable in DB2 that is always “true”. Then related this variable to the calculated variable in DB1. The drop down menu is properly set up to show only related values. Nothing shows. I established a test variable to “count” the number of related values, and get “?”. A portal to DB1 also shows no patients.

Suggestions?

I don't think it's possible to identify the problem based only on your description.  Why not attach a simple file that shows the problem (and preferably only the problem)?

In any case, I believe you could make this simpler: just define a calculation field in the Admissions table that returns the patient's ID if the patient is still in the hospital. Then use this field for your value list. There is no need for an additional relationship.