All tidying methods return a data.frame without rownames, whose
structure depends on the method chosen.
tidy
on "survdiff" objects returns a data frame with the following columns:
...initial column(s) correspond to grouping factors (right-hand side of the formula)
obsweighted observed number of events in each group
expweighted expected number of events in each group
Nnumber of subjects in each group
glance on "survdiff" objects returns a data frame with the following columns:
statisticvalue of the test statistic
dfdegrees of freedom
p.valuep-value