diff --git a/DESCRIPTION b/DESCRIPTION
index f31d3e1a..c90753c5 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -10,7 +10,7 @@ Description: Automates fixed item parameter linking for test linking under
     the item response theory paradigm using mirt package estimates.
 License: GPL-3 | file LICENSE
 Imports: mirt, methods
-Suggests: testthat (>= 3.0.0)
+Suggests: testthat (>= 3.0.0), mockery
 Encoding: UTF-8
 Config/testthat/edition: 3
 Config/roxygen2/version: 8.0.0
diff --git a/R/aFIPC.R b/R/aFIPC.R
index 62546519..918e19b1 100644
--- a/R/aFIPC.R
+++ b/R/aFIPC.R
@@ -141,7 +141,7 @@ autoFIPC <-
       }
       for (attempt in seq_len(3)) {
         n <- readline(prompt = "Is it correct? (1: Yes 2: No) : ")
-        if (grepl("^[0-9]+$", n)) {
+        if (grepl("^[12]$", n)) {
           return(as.integer(n))
         }
       }
@@ -171,7 +171,7 @@ autoFIPC <-
               readline(
                 prompt = "Do you want to use default BILOG-MG priors for oldform Data? (1: Yes 2: No) : "
               )
-            if (grepl("^[0-9]+$", n)) {
+            if (grepl("^[12]$", n)) {
               return(as.integer(n))
             }
           }
@@ -390,7 +390,7 @@ autoFIPC <-
               readline(
                 prompt = "Do you want to use default BILOG-MG priors for newform Data? (1: Yes 2: No) : "
               )
-            if (grepl("^[0-9]+$", n)) {
+            if (grepl("^[12]$", n)) {
               return(as.integer(n))
             }
           }
diff --git a/tests/testthat/test-interactive-choice-validation.R b/tests/testthat/test-interactive-choice-validation.R
new file mode 100644
index 00000000..6ddb4670
--- /dev/null
+++ b/tests/testthat/test-interactive-choice-validation.R
@@ -0,0 +1,77 @@
+test_that("common-item confirmation rejects values outside 1 or 2", {
+  mockery::stub(aFIPC::autoFIPC, "interactive", TRUE)
+  mock_readline <- mockery::mock("0", "3", "12", cycle = TRUE)
+  mockery::stub(aFIPC::autoFIPC, "readline", mock_readline)
+
+  expect_error(
+    aFIPC::autoFIPC(
+      newformXData = data.frame(new_item_1 = c(1, 0, 1)),
+      oldformYData = data.frame(old_item_1 = c(0, 1, 0)),
+      newformCommonItemNames = "new_item_1",
+      oldformCommonItemNames = "old_item_1",
+      confirmCommonItems = NULL
+    ),
+    "Too many invalid common item confirmation attempts"
+  )
+})
+
+test_that("old-form prior prompt rejects malformed and out-of-range choices", {
+  mockery::stub(aFIPC::autoFIPC, "interactive", TRUE)
+  oversized_integer <- paste(rep("9", 1000), collapse = "")
+  mock_readline <- mockery::mock(" 1", "abc", oversized_integer, cycle = TRUE)
+  mockery::stub(aFIPC::autoFIPC, "readline", mock_readline)
+
+  test_data <- data.frame(
+    item1 = rep(c(0, 1), 50),
+    item2 = rep(c(1, 0), 50),
+    item3 = rep(c(0, 0, 1, 1), 25)
+  )
+
+  expect_error(
+    aFIPC::autoFIPC(
+      newformXData = test_data,
+      oldformYData = test_data,
+      newformCommonItemNames = c("item1", "item2"),
+      oldformCommonItemNames = c("item1", "item2"),
+      confirmCommonItems = TRUE,
+      itemtype = "3PL",
+      oldformBILOGprior = NULL
+    ),
+    "Too many invalid oldform BILOG prior attempts"
+  )
+})
+
+test_that("new-form prior prompt rejects malformed and out-of-range choices", {
+  mockery::stub(aFIPC::autoFIPC, "interactive", TRUE)
+  oversized_integer <- paste(rep("9", 1000), collapse = "")
+  mock_readline <- mockery::mock("1", "3", "abc", oversized_integer, cycle = TRUE)
+  mockery::stub(aFIPC::autoFIPC, "readline", mock_readline)
+
+  # autoFIPC reads these mirt slots directly before reaching the new-form prompt.
+  fake_model <- new("SingleGroupClass")
+  fake_model@OptimInfo <- list(secondordertest = TRUE)
+  fake_model@Data <- list(K = c(2, 2))
+
+  mockery::stub(aFIPC::autoFIPC, "mirt::mirt", fake_model)
+  mockery::stub(aFIPC::autoFIPC, "mirt::multipleGroup", fake_model)
+  mockery::stub(aFIPC::autoFIPC, "aFIPC:::make_aFIPC_model", fake_model)
+
+  test_data <- data.frame(
+    item1 = c(1, 0, 1, 0, 1),
+    item2 = c(0, 1, 0, 1, 0)
+  )
+
+  expect_error(
+    aFIPC::autoFIPC(
+      newformXData = test_data,
+      oldformYData = test_data,
+      newformCommonItemNames = "item1",
+      oldformCommonItemNames = "item1",
+      confirmCommonItems = TRUE,
+      itemtype = "3PL",
+      oldformBILOGprior = NULL,
+      newformBILOGprior = NULL
+    ),
+    "Too many invalid newform BILOG prior attempts"
+  )
+})