Prejudice, science, etc.

[zenmaster]

why do you need a scientific theory to find positive test results valid?

No one said you do.

Aren't theories devised because of positive test results of effects?

No. The experimental results may suggest an underlying principle. That's what a theory attempts to address.

The most common, stereotypical telepathic experiment is "guessing" the suit of the next card flipped over. Since there are 4 suits, if there is no telepathy, people should be guessing correctly at 25% the time. The hit rate for the meta data(with trials dating back to the 1930's) on that specific type of experiment is 34%, implying some sort interesting effect going on.

That is correct. It's called "anecdotal evidence" and, on its own, does nothing to further understanding. The better the experiment (the more understanding involved), the more likely it may be reliably reproduced (i.e. you do this, you get this).