TEST Statement

The MULTTEST Procedure

TEST Statement

TEST name ( variables < / options >) ;

The TEST statement is required. It identifies statistical tests to be performed and the discrete and continuous variables to be tested. The following tests are permitted as name in the TEST statement.

requests the Cochran-Armitage linear trend tests for group comparisons. The test variables should take the value 0 for a failure and 1 for a success. The PERMUTATION= option can be used to request an exact permutation test; otherwise, a Z-score approximation is used. The CONTINUITY= option can be used to specify a continuity correction for the Z-score approximation.

FISHER	requests Fisher exact tests for comparing two treatment groups. The test variables should take the value 0 for a failure and 1 for a success.
FT	requests Z-score CA tests based upon the Freeman-Tukey double arcsine transformation of the frequencies. The test variables should take the value 0 for a failure and 1 for a success.
MEAN	requests the t-test for the mean. The test variables can take on any numeric values.
PETO	requests the Peto mortality-prevalence test. The test variables should take the value 0 for a failure, 1 for a success, and 2 for a fatality. The TIME= option should be used with the PETO test to specify a variable giving the age at death. The CONTINUITY= option can be used to specify a continuity correction for the test.

If the value of a TEST variable is invalid, the observation is not used in the analysis. You can specify two tests only if one of them is MEAN. For example, the following statement is valid

   test ca(d1-d2) mean(c1-c2);

but the statement

   test ca(d1-d2) ft(d1-d2);

is invalid.

You can specify the following options in the TEST statement (some apply to only one test).

BINOMIAL: specifies that the binomial variance estimate be used for CA and PETO tests in their asymptotic normal approximations. The default is to use the hypergeometric variance.
CONTINUITY= number
C= number: specifies number as a particular continuity correction for the Z-score approximation in the CA and PETO tests. The default is 0.
LOWERTAILED
LOWER: is used to make all tests lower-tailed. All tests are two-tailed by default.
PERMUTATION= number
PERM= number: specifies that p-values for the CA and PETO tests be computed using exact permutation distributions when marginal success or failure totals within a stratum are number or less. For values greater than number (or when the PERMUTATION= option is omitted), PROC MULTTEST uses standard normal approximations with a continuity correction chosen to approximate the permutation distribution. PROC MULTTEST computes the appropriate convolution distributions when you use the STRATA statement along with the PERMUTATION= option.
TIME= variable: identifies the PETO test variable containing the age at death, which is assumed to be integer valued. If the TIME= option is omitted, all ages are assumed to equal 1.
UPPERTAILED
UPPER: is used to make all tests upper-tailed. All tests are two-tailed by default.

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