diff --git a/mod/quiz/classes/question/qubaids_for_quiz.php b/mod/quiz/classes/question/qubaids_for_quiz.php
index 9fdca446b79..e42a650a838 100644
--- a/mod/quiz/classes/question/qubaids_for_quiz.php
+++ b/mod/quiz/classes/question/qubaids_for_quiz.php
@@ -23,11 +23,21 @@ require_once($CFG->dirroot . '/question/engine/datalib.php');
 /**
  * A {@see qubaid_condition} for finding all the question usages belonging to a particular quiz.
  *
- * @copyright  2010 The Open University
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   mod_quiz
+ * @category  question
+ * @copyright 2010 The Open University
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class qubaids_for_quiz extends \qubaid_join {
-    public function __construct($quizid, $includepreviews = true, $onlyfinished = false) {
+
+    /**
+     * Constructor.
+     *
+     * @param int $quizid The quiz to search.
+     * @param bool $includepreviews Whether to include preview attempts
+     * @param bool $onlyfinished Whether to only include finished attempts or not
+     */
+    public function __construct(int $quizid, bool $includepreviews = true, bool $onlyfinished = false) {
         $where = 'quiza.quiz = :quizaquiz';
         $params = array('quizaquiz' => $quizid);
 
diff --git a/mod/quiz/classes/question/qubaids_for_quiz_user.php b/mod/quiz/classes/question/qubaids_for_quiz_user.php
index b83d1b8ca4d..33b764153f4 100644
--- a/mod/quiz/classes/question/qubaids_for_quiz_user.php
+++ b/mod/quiz/classes/question/qubaids_for_quiz_user.php
@@ -16,41 +16,28 @@
 
 namespace mod_quiz\question;
 
-defined('MOODLE_INTERNAL') || die();
-
-require_once($CFG->dirroot . '/question/engine/datalib.php');
-
 /**
  * A {@see qubaid_condition} for finding all the question usages belonging to a particular user and quiz combination.
  *
- * @copyright  2018 Andrew Nicols <andrwe@nicols.co.uk>
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package   mod_quiz
+ * @category  question
+ * @copyright 2018 Andrew Nicols <andrwe@nicols.co.uk>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @deprecated This class was never needed because qubaids_for_users_attempts already existed and is more flexible.
  */
-class qubaids_for_quiz_user extends \qubaid_join {
+class qubaids_for_quiz_user extends qubaids_for_users_attempts {
     /**
-     * Constructor for this qubaid.
+     * Constructor.
      *
-     * @param   int     $quizid The quiz to search.
-     * @param   int     $userid The user to filter on
-     * @param   bool    $includepreviews Whether to include preview attempts
-     * @param   bool    $onlyfinished Whether to only include finished attempts or not
+     * @param int $quizid The quiz to search.
+     * @param int $userid The user to filter on
+     * @param bool $includepreviews Whether to include preview attempts
+     * @param bool $onlyfinished Whether to only include finished attempts or not
      */
-    public function __construct($quizid, $userid, $includepreviews = true, $onlyfinished = false) {
-        $where = 'quiza.quiz = :quizaquiz AND quiza.userid = :quizauserid';
-        $params = [
-            'quizaquiz' => $quizid,
-            'quizauserid' => $userid,
-        ];
-
-        if (!$includepreviews) {
-            $where .= ' AND preview = 0';
-        }
-
-        if ($onlyfinished) {
-            $where .= ' AND state = :statefinished';
-            $params['statefinished'] = quiz_attempt::FINISHED;
-        }
-
-        parent::__construct('{quiz_attempts} quiza', 'quiza.uniqueid', $where, $params);
+    public function __construct(int $quizid, int $userid,
+            bool $includepreviews = true, bool $onlyfinished = false) {
+        debugging('qubaids_for_quiz_user is deprecated. Please use qubaids_for_users_attempts instead.');
+        parent::__construct($quizid, $userid,
+                $onlyfinished ? 'finished' : 'all', $includepreviews);
     }
 }
diff --git a/mod/quiz/classes/question/qubaids_for_users_attempts.php b/mod/quiz/classes/question/qubaids_for_users_attempts.php
index 55e22fa54f1..b3c102ca835 100644
--- a/mod/quiz/classes/question/qubaids_for_users_attempts.php
+++ b/mod/quiz/classes/question/qubaids_for_users_attempts.php
@@ -14,24 +14,18 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
 
-/**
- * A {@link qubaid_condition} representing all the attempts by one user at a given quiz.
- *
- * @package   mod_quiz
- * @category  question
- * @copyright 2015 The Open University
- * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
-
 namespace mod_quiz\question;
 
 defined('MOODLE_INTERNAL') || die();
 
+require_once($CFG->dirroot . '/question/engine/datalib.php');
 require_once($CFG->dirroot.'/mod/quiz/attemptlib.php');
 
 /**
- * A {@link qubaid_condition} representing all the attempts by one user at a given quiz.
+ * A {@see qubaid_condition} representing all the attempts by one user at a given quiz.
  *
+ * @package   mod_quiz
+ * @category  question
  * @copyright 2015 The Open University
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
@@ -48,7 +42,7 @@ class qubaids_for_users_attempts extends \qubaid_join {
      */
     public function __construct($quizid, $userid, $status = 'finished', $includepreviews = false) {
         $where = 'quiza.quiz = :quizaquiz AND quiza.userid = :userid';
-        $params = array('quizaquiz' => $quizid, 'userid' => $userid);
+        $params = ['quizaquiz' => $quizid, 'userid' => $userid];
 
         if (!$includepreviews) {
             $where .= ' AND preview = 0';
diff --git a/mod/quiz/classes/structure.php b/mod/quiz/classes/structure.php
index 62122766e16..b88a02edb83 100644
--- a/mod/quiz/classes/structure.php
+++ b/mod/quiz/classes/structure.php
@@ -1044,7 +1044,7 @@ class structure {
         $previousmaxmark = $slot->maxmark;
         $slot->maxmark = $maxmark;
         $DB->update_record('quiz_slots', $slot);
-        \question_engine::set_max_mark_in_attempts(new \qubaids_for_quiz($slot->quizid),
+        \question_engine::set_max_mark_in_attempts(new qubaids_for_quiz($slot->quizid),
                 $slot->slot, $maxmark);
         $trans->allow_commit();
 
diff --git a/mod/quiz/lib.php b/mod/quiz/lib.php
index ca6bf1f8eb1..9d95b82931a 100644
--- a/mod/quiz/lib.php
+++ b/mod/quiz/lib.php
@@ -31,6 +31,7 @@ defined('MOODLE_INTERNAL') || die();
 use mod_quiz\question\bank\custom_view;
 use mod_quiz\question\display_options;
 use mod_quiz\question\qubaids_for_quiz;
+use mod_quiz\question\qubaids_for_users_attempts;
 use core_question\statistics\questions\all_calculated_for_qubaid_condition;
 
 require_once($CFG->dirroot . '/calendar/lib.php');
@@ -416,7 +417,8 @@ function quiz_delete_all_attempts($quiz) {
 function quiz_delete_user_attempts($quiz, $user) {
     global $CFG, $DB;
     require_once($CFG->dirroot . '/mod/quiz/locallib.php');
-    question_engine::delete_questions_usage_by_activities(new qubaids_for_quiz_user($quiz->get_quizid(), $user->id));
+    question_engine::delete_questions_usage_by_activities(new qubaids_for_users_attempts(
+            $quiz->get_quizid(), $user->id, 'all'));
     $params = [
         'quiz' => $quiz->get_quizid(),
         'userid' => $user->id,
diff --git a/mod/quiz/upgrade.txt b/mod/quiz/upgrade.txt
index 416826e48bc..2c136eed71a 100644
--- a/mod/quiz/upgrade.txt
+++ b/mod/quiz/upgrade.txt
@@ -8,7 +8,8 @@ This files describes API changes in the quiz code.
   doable by adding use statements, and a search/replace.
   - mod_quiz_display_options => mod_quiz\question\display_options
   - qubaids_for_quiz => mod_quiz\question\qubaids_for_quiz
-  - qubaids_for_quiz_user => mod_quiz\question\qubaids_for_quiz_user
+  - qubaids_for_quiz_user => mod_quiz\question\qubaids_for_quiz_user - which is deprecated, because
+          it is almost the same as mod_quiz\question\qubaids_for_users_attempts.
 
 
 === 4.1 ===