diff --git a/modules/document/document.controller.php b/modules/document/document.controller.php
index c8e54b5ec..dc3e0506b 100644
--- a/modules/document/document.controller.php
+++ b/modules/document/document.controller.php
@@ -889,7 +889,7 @@ class DocumentController extends Document
 					if (!$manual_inserted)
 					{
 						$ev_output = $extra_item->validate($value);
-						if ($ev_output && !$output->toBool())
+						if ($ev_output && !$ev_output->toBool())
 						{
 							$oDB->rollback();
 							return $ev_output;