Conversation so far:
Who first tested Garret's abilities?
One of the tests was organized by Joseph Rhine at Duke University in 1933 which involved Zener cards.
Describe the test?
Certain symbols that were placed on the cards and sealed in an envelope, and participants were asked to guess their contents.

Question: What were the results of the test?
Self-contained rewrite: What were the results of Joseph Rhine's test in 1933?