help for ^symmetry^                                      (Statalist distributio
> n)

Symmetry and Marginal Homogeneity test for matched samples/ TDT test - --------------------------------------------------------------------

^symmetry^ var_cases var_controls [^if^ exp] [^in^ range] [^,^ ^not^able ^con^ > trib ^ex^act]

Description - -----------

^symmetry^ performs symmetry and marginal homogeneity tests on square NxN tables where there is a 1 to 1 matching of cases and controls (non-independence). In genetics, the test is known as the Transmission/Disequilibrium test (TDT) and is used to test the association between transmitted and non-transmitted parental marker alleles to an affected child.

Options - -------

^notable^ suppresses the output of the contingency table.

^contrib^ reports the contribution of each off-diagonal cell-pair to the overall symmetry chi-square.

^exact^ performs an exact test of table symmetry. CAUTION: the exact test requires substantial amounts of time and memory for large tables.

Examples - --------

. ^symmetry cases controls^ . ^symmetry cases controls, not^ . ^symmetry cases controls, con^ . ^symmetry cases controls, not con^ . ^symmetry cases controls, ex con^

Author - ------

Mario Cleves <mcleves@@stata.com>.

Also see - --------

On-line: @epitab@