For example, if flipping a coin, testing whether it is biased "towards" heads is a one-tailed test, and getting data of "all heads" would be seen as highly significant, while getting data of "all tails" would be not significant at all ("p" = 1). By contrast, testing whether it is biased in "either" direction is a two-tailed test, and either "all heads" or "all tails" would both be seen as highly significant data. In medical testing, while one is generally interested in whether a treatment results in outcomes that are "better" than chance, thus suggesting a one-tailed test; a "worse" outcome is also interesting for the scientific field, therefore one should use a two-tailed test that corresponds instead to testing whether the treatment results in outcomes that are "different" from chance, either better or worse. In the archetypal lady tasting tea experiment, Fisher tested whether the lady in question was "better" than chance at distinguishing two types of tea preparation, not whether her ability was "different" from chance, and thus he used a one-tailed test.