It is important that statistical tests should be reliable for small samples and rare events. Permutation tests (1) form an important class of tests that can provide “exact” results for small samples. Permutation tests themselves, however, have limitations which must be realized if they are to be used reliably. The paper shows, by illustrative examples, some uses and limitations of permutation tests.
EdgingtonES. Randomization tests.New York, NY: Marcel Dekker, Inc.; 1980.
2.
LiddellD. Practical tests of 2 × 2 contingency tables. Statistic.1978;25:295–304.
3.
SuissaSShusterJJ. Exact unconditional sample sizes for the 2 × 2 binomial trial. J Roy Stat Soc, Series A.1985;148(4):317–327.
4.
GartJJKrewskiDLeePNTaroneREWahrendorfJ. Statistical Methods in Cancer Research. Volume III—The design and analysis of long-term animal experiments. IARC Scientific Publications No. 79. Lyon, France; International Agency for Research on Cancer; 1986;79:167–168.
5.
MehtaCPatelN. StatXact User Manual.Cambridge, MA: Cytel Software Corp.; 1985.
6.
BarnardGA. On alleged gains in power from lower p-values. Stat Med.1989;8:1469–1477.
