The methods actually use xtableList,
because of its ability to display messages such as those for P-value
adjustments. These methods return an object of class "xtable_emm" --
an extension of "xtableList". Unlike other xtable methods, the
number of digits defaults to 4; and degrees of freedom and t ratios
are always formatted independently of digits. The print method
uses print.xtableList, and any ... arguments are
passed there.