diff --git a/R/aFIPC.R b/R/aFIPC.R
index 62546519..3f336635 100644
--- a/R/aFIPC.R
+++ b/R/aFIPC.R
@@ -613,10 +613,10 @@ autoFIPC <-
     if (checkIPD == T) {
       # config
       IPDgroup <-
-        as.factor(c(
+        factor(c(
           rep('oldForm', nrow(oldformYDataK)),
           rep('newForm', nrow(newformXDataK))
-        ))
+        ), levels = c('newForm', 'oldForm'))
       IPDItemCount <- 0
 
       # IPD target item checking
diff --git a/tests/testthat/test-ipdgroup-factor-equivalence.R b/tests/testthat/test-ipdgroup-factor-equivalence.R
new file mode 100644
index 00000000..a7527366
--- /dev/null
+++ b/tests/testthat/test-ipdgroup-factor-equivalence.R
@@ -0,0 +1,19 @@
+test_that("explicit IPD group levels preserve the protected factor contract", {
+  cardinalities <- list(
+    c(old_form = 1L, new_form = 1L),
+    c(old_form = 3L, new_form = 5L),
+    c(old_form = 37L, new_form = 61L)
+  )
+
+  for (sizes in cardinalities) {
+    labels <- c(
+      rep("oldForm", sizes[["old_form"]]),
+      rep("newForm", sizes[["new_form"]])
+    )
+    protected <- as.factor(labels)
+    candidate <- factor(labels, levels = c("newForm", "oldForm"))
+
+    expect_identical(candidate, protected)
+    expect_identical(levels(candidate), c("newForm", "oldForm"))
+  }
+})