diff --git a/classes/anonymous.php b/classes/anonymous.php
index d0072efa09..def6176e82 100644
--- a/classes/anonymous.php
+++ b/classes/anonymous.php
@@ -65,7 +65,7 @@ public static function is_post_anonymous($discussion, $moodleoverflow, $postingu
         }
 
         if ($moodleoverflow->anonymous == self::QUESTION_ANONYMOUS) {
-            return $discussion->userid == $postinguserid;
+            return $discussion->get_userid() == $postinguserid;
         }
 
         return false;