Create a "summary" table to collect the data for each patient (assuming patient ID is a key). The columns would look like Study 1 Current Timepoint, Study 1 1-Month Visit, etc. Then build a pipeline that triggers on edit to perform a copy records from Study 1 table to the fields in the summary table. Build your dashboard report off of the summary table to show the columns desired.
You might could do the same with a relationship from each Study table to the Summary table, but have to get the patient ID (or other key) in the summary table for the lookups to collect the data.
Depending on how many patients you have, you may want to use a button on your dashboard to take them to the report. Ask some filtering questions first and then display the results. Each time you have a report on a dashboard home tab it will pull all that data before it can load and display.
