diff --git a/R/Methods.R b/R/Methods.R
index 4e2232e..e0e38ef 100644
--- a/R/Methods.R
+++ b/R/Methods.R
@@ -156,8 +156,7 @@ setMethod("Summary",
         dimnames = list(colnames(n), c("median", "lower", "upper"))
       )
       HPD[, 1] <- colMedians(n, na.rm = na.rm)
-      ind_not_na <- !is.na(HPD[, 1])
-      HPD[ind_not_na, 2:3] <- apply(n[, ind_not_na], 2, function(col) {
+      HPD[, 2:3] <- apply(n, 2, function(col) {
         if (na.rm) {
           col <- na.omit(col)
         }
diff --git a/man/Summary-BASiCS_Chain-method.Rd b/man/Summary-BASiCS_Chain-method.Rd
index 7954e6c..d71ccc9 100644
--- a/man/Summary-BASiCS_Chain-method.Rd
+++ b/man/Summary-BASiCS_Chain-method.Rd
@@ -6,7 +6,7 @@
 \alias{Summary,BASiCS_Chain-method}
 \title{'Summary' method for BASiCS_Chain objects}
 \usage{
-\S4method{Summary}{BASiCS_Chain}(x, prob = 0.95, na.rm = FALSE)
+\S4method{Summary}{BASiCS_Chain}(x, ..., prob = 0.95, na.rm = FALSE)
 }
 \arguments{
 \item{x}{A \code{\linkS4class{BASiCS_Chain}} object.}
diff --git a/tests/testthat/test_methods.R b/tests/testthat/test_methods.R
index 70ded1c..9d4d8c9 100644
--- a/tests/testthat/test_methods.R
+++ b/tests/testthat/test_methods.R
@@ -19,6 +19,8 @@ test_that("Summary na.rm", {
   expect_false(any(is.na(s1@parameters$nu)))
   expect_true(all(is.na(s2@parameters$nu[1, ])))
   expect_true(all(is.na(s2@parameters$nu[4, ])))
+  ChainSC@parameters$nu[1, 1:ncol(ChainSC@parameters$nu)] <- NA
+  expect_error(s3 <- Summary(ChainSC, na.rm = TRUE))
 })
 
 test_that("subset", {