diff --git a/php/libraries/NDB_BVL_Instrument.class.inc b/php/libraries/NDB_BVL_Instrument.class.inc
index e9f546c7bda..5438941f523 100644
--- a/php/libraries/NDB_BVL_Instrument.class.inc
+++ b/php/libraries/NDB_BVL_Instrument.class.inc
@@ -195,7 +195,7 @@ abstract class NDB_BVL_Instrument extends NDB_Page
     /**
      * Array containing all multiselect elements in an instrument.
      */
-    protected $selectMultipleElements;
+    protected $selectMultipleElements = [];
 
     /**
      * Factory generates a new instrument instance of type
@@ -3105,4 +3105,15 @@ abstract class NDB_BVL_Instrument extends NDB_Page
 
         return $instrumentNames;
     }
+
+    /**
+     * Gets the current instrument instance selectMultipleElements
+     *
+     * @return array the select multiple elements of this instrument.
+     * @access public
+     */
+    public function getSelectMultipleElements(): array
+    {
+        return $this->selectMultipleElements;
+    }
 }