Astrology has not demonstrated its effectiveness in controlled studies and has no scientific validity.:85; Where it has made falsifiable predictions under controlled conditions, they have been falsified.
One famous experiment included 28 astrologers who were asked to match over a hundred natal charts to psychological profiles generated by the California Psychological Inventory (CPI) questionnaire. The double-blind experimental protocol used in this study was agreed upon by a group of physicists and a group of astrologers nominated by the National Council for Geocosmic Research, who advised the experimenters, helped ensure that the test was fair:420;:117 and helped draw the central proposition of natal astrology to be tested.:419 They also chose 26 out of the 28 astrologers for the tests (two more volunteered afterwards).:420 The study, published in Nature in 1985, found that predictions based on natal astrology were no better than chance, and that the testing "...clearly refutes the astrological hypothesis."