diff --git a/mod/quiz/report/overview/report.php b/mod/quiz/report/overview/report.php
index d9262cd9010..81b2dc2b1cf 100644
--- a/mod/quiz/report/overview/report.php
+++ b/mod/quiz/report/overview/report.php
@@ -397,14 +397,6 @@ class quiz_overview_report extends attempts_report {
         return $messages;
     }
 
-    /**
-     * For use in tests only. Clear the cached regrade data.
-     */
-    public function clear_regrade_date_cache(): void {
-        $this->structureforregrade = null;
-        $this->newquestionidsforold = null;
-    }
-
     /**
      * Regrade attempts for this quiz, exactly which attempts are regraded is
      * controlled by the parameters.
diff --git a/mod/quiz/report/overview/tests/report_test.php b/mod/quiz/report/overview/tests/report_test.php
index 0e553df77f4..f7b13bb244e 100644
--- a/mod/quiz/report/overview/tests/report_test.php
+++ b/mod/quiz/report/overview/tests/report_test.php
@@ -398,7 +398,6 @@ class report_test extends \advanced_testcase {
 
         // Now change the quiz back to always latest and regrade again.
         submit_question_version::execute($slot->slotid, 0);
-        $report->clear_regrade_date_cache();
         $report->regrade_attempt($attempt);
 
         // Score should now be 5, because v3 is the latest non-draft version.