diff --git a/mod/quiz/index.php b/mod/quiz/index.php
index 71c0f335375..e8f2986f8e3 100644
--- a/mod/quiz/index.php
+++ b/mod/quiz/index.php
@@ -112,10 +112,17 @@
                 $gradecol = "";
             }
         } else {
+            // If student has no grade for this quiz, 
+            // or the quiz has no grade, display nothing in grade col
             if ($bestgrade === NULL || $quiz->grade == 0) {
                 $gradecol = "";
             } else {
-                $gradecol = "$bestgrade / $quiz->grade";
+                //If all quiz's attempts have visible results, show bestgrade
+                if(all_attempt_results_visible($quiz, $USER)) {
+                    $gradecol = "$bestgrade / $quiz->grade";
+                } else {
+                    $gradecol = "";
+                }
             }
         }
 
diff --git a/mod/quiz/locallib.php b/mod/quiz/locallib.php
index 5fcea170a4f..afd76708581 100644
--- a/mod/quiz/locallib.php
+++ b/mod/quiz/locallib.php
@@ -550,5 +550,31 @@ function quiz_get_reviewoptions($quiz, $attempt, $isteacher=false) {
 
     return $options;
 }
+////////////////////////////////////////////////////////////////////////////////
+/**
+* Return boolean indicating if the quiz has attempts with hidden grades
+*
+* Selects all attempts matching specified quiz & user, and examines each to
+* check they all have visible results.
+* @return boolean        If the quiz has attempts without visible results
+* @param object $quiz    The quiz being examined
+* @param object $user    The user concerned
+*/
+function all_attempt_results_visible($quiz, $user) {
+    global $CFG;
+    $sql = 'SELECT timefinish, preview FROM '.$CFG->prefix.'quiz_attempts qa'.
+        ' WHERE qa.quiz='.$quiz->id.' AND qa.userid='.$user->id.
+        ' ORDER BY id DESC';
+    $attempts = get_records_sql($sql);
+    foreach ($attempts as $attempt) {            
+        $attemptoptions = quiz_get_reviewoptions($quiz, $attempt);
+        //if any attempt has scores option not set, not all attempt results are
+        //visible
+        if (!$attemptoptions->scores) {
+           return false;
+        }
+    }
+    return true;
+}
 
 ?>