smd for weighted data

DESCRIPTION

@@ -28,6 +28,7 @@ Suggests:
     effectsize (>= 0.6.0),
     parameters (>= 0.20.2),
     smd (>= 0.6.6),
+    survey (>= 4.1),
     spelling,
     testthat (>= 3.2.0),
     withr

R/ard_smd.R

@@ -25,6 +25,15 @@ ard_smd <- function(data, by, variable, ...) {
   check_not_missing(data)
   check_not_missing(variable)
   check_not_missing(by)
+
+  # grab design object if from `survey` ----------------------------------------
+  is_survey <- inherits(data, "survey.design")
+  if (is_survey) {
+    design <- data
+    data <- design$variables
+  }
+
+  # continue check/process inputs ----------------------------------------------
   check_data_frame(data)
   data <- dplyr::ungroup(data)
   cards::process_selectors(data, by = {{ by }}, variable = {{ variable }})
@@ -37,7 +46,11 @@ ard_smd <- function(data, by, variable, ...) {
     variable = variable,
     lst_tidy =
       cards::eval_capture_conditions(
-        smd::smd(x = data[[variable]], g = data[[by]], na.rm = TRUE, ...) |>
+        switch(
+         as.character(is_survey),
+         "TRUE" = smd::smd(x = data[[variable]], g = data[[by]], w = stats::weights(design), na.rm = TRUE, ...),
+         "FALSE" = smd::smd(x = data[[variable]], g = data[[by]], na.rm = TRUE, ...)
+        ) |>
           dplyr::select(-any_of("term"))
       ),
     ...

tests/testthat/test-ard_smd.R

@@ -18,6 +18,28 @@ test_that("ard_smd() works", {
   )
 })
 
+test_that("ard_smd() works with survey data", {
+  skip_if_not(cards::is_pkg_installed("survey", reference_pkg = "cardx"))
+  data(api, package = "survey")
+  dclus1 <- survey::svydesign(id=~dnum, weights=~pw, data=apiclus1, fpc=~fpc)
+
+  expect_error(
+    ard_smd <-
+      dclus1 |>
+      ard_smd(by = both, variable = api00, std.error = TRUE),
+    NA
+  )
+
+  expect_equal(
+    ard_smd |>
+      cards::get_ard_statistics(stat_name %in% c("estimate", "std.error")),
+    smd::smd(x = apiclus1$api00, g = apiclus1$both, w = weights(dclus1), std.error = TRUE) |>
+      dplyr::select(-term) |>
+      unclass(),
+    ignore_attr = TRUE
+  )
+})
+
 test_that("ard_proptest() error messaging", {
   # mis-specify the gref argument
   expect_error(