Add differences between groups

Source: R/add_difference.tbl_svysummary.R

Adds difference to tables created by tbl_summary(). The difference between two groups (typically mean or rate difference) is added to the table along with the difference's confidence interval and a p-value (when applicable).

# S3 method for class 'tbl_svysummary'
add_difference(
  x,
  test = NULL,
  group = NULL,
  adj.vars = NULL,
  test.args = NULL,
  conf.level = 0.95,
  include = everything(),
  pvalue_fun = label_style_pvalue(digits = 1),
  estimate_fun = list(c(all_continuous(), all_categorical(FALSE)) ~ label_style_sigfig(),
    all_dichotomous() ~ label_style_sigfig(scale = 100, suffix = "%"), all_tests("smd")
    ~ label_style_sigfig()),
  ...
)

Arguments

x

(tbl_summary)
table created with tbl_summary()

test

(formula-list-selector)
Specifies the tests/methods to perform for each variable, e.g. list(all_continuous() ~ "t.test", all_dichotomous() ~ "prop.test", all_categorical(FALSE) ~ "smd").

See below for details on default tests and ?tests for details on available tests and creating custom tests.

group

(tidy-select)
Variable name of an ID or grouping variable. The column can be used to calculate p-values with correlated data. Default is NULL. See tests for methods that utilize the group argument.

adj.vars

(tidy-select)
Variables to include in adjusted calculations (e.g. in ANCOVA models). Default is NULL.

test.args

(formula-list-selector)
Containing additional arguments to pass to tests that accept arguments. For example, add an argument for all t-tests, use test.args = all_tests("t.test") ~ list(var.equal = TRUE).

conf.level

(numeric)
a scalar in the interval (0, 1) indicating the confidence level. Default is 0.95

include

(tidy-select)
Variables to include in output. Default is everything().

pvalue_fun

(function)
Function to round and format p-values. Default is label_style_pvalue(). The function must have a numeric vector input, and return a string that is the rounded/formatted p-value (e.g. pvalue_fun = label_style_pvalue(digits = 2)).

estimate_fun

(formula-list-selector)
List of formulas specifying the functions to round and format differences and confidence limits. Default is list(c(all_continuous(), all_categorical(FALSE)) ~ label_style_sigfig(), all_categorical() ~ \(x) paste0(style_sigfig(x, scale = 100), "%"))

...

These dots are for future extensions and must be empty.

Value

a gtsummary table of class "tbl_summary"

Examples