diff --git a/completion/completion_completion.php b/completion/completion_completion.php
index 18c78dceb8a..4e0a33c4436 100644
--- a/completion/completion_completion.php
+++ b/completion/completion_completion.php
@@ -161,17 +161,7 @@ class completion_completion extends data_object {
         // Save record.
         if ($result = $this->_save()) {
             $data = $this->get_record_data();
-            $event = \core\event\course_completed::create(
-                array(
-                    'objectid' => $data->id,
-                    'userid' => $USER->id,
-                    'relateduserid' => $data->userid,
-                    'context' => context_course::instance($data->course),
-                    'courseid' => $data->course
-                    )
-                );
-            $event->add_record_snapshot('course_completions', $data);
-            $event->trigger();
+            \core\event\course_completed::create_from_completion($data)->trigger();
         }
 
         return $result;
diff --git a/course/tests/courselib_test.php b/course/tests/courselib_test.php
index fac80f951d9..0ff62dd45ec 100644
--- a/course/tests/courselib_test.php
+++ b/course/tests/courselib_test.php
@@ -1813,7 +1813,7 @@ class core_course_courselib_testcase extends advanced_testcase {
         $this->assertEquals($course->id, $event->courseid);
         $this->assertEquals($coursecontext->id, $event->contextid);
         $this->assertEquals($section->section, $event->other['sectionnum']);
-        $expecteddesc = 'Course ' . $event->courseid . ' section ' . $event->other['sectionnum'] . ' updated by user ' . $event->userid;
+        $expecteddesc = "The user with the id '{$event->userid}' updated the section with the number '{$event->other['sectionnum']}' for the course with the id '{$event->courseid}'";
         $this->assertEquals($expecteddesc, $event->get_description());
         $url = new moodle_url('/course/editsection.php', array('id' => $event->objectid));
         $this->assertEquals($url, $event->get_url());
diff --git a/lib/classes/event/course_completed.php b/lib/classes/event/course_completed.php
index 32e129ef618..705251d6d0e 100644
--- a/lib/classes/event/course_completed.php
+++ b/lib/classes/event/course_completed.php
@@ -29,12 +29,37 @@ defined('MOODLE_INTERNAL') || die();
 /**
  * Course completed event class.
  *
+ * @property-read int $relateduserid user who completed the course
+ * @property-read array $other {
+ *      Extra information about event.
+ *
+ *      - int relateduserid: deprecated since 2.7, please use property relateduserid
+ * }
+ *
  * @package    core
  * @since      Moodle 2.6
  * @copyright  2013 Rajesh Taneja <rajesh@moodle.com>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 class course_completed extends base {
+    /**
+     * Create event from course_completion record.
+     * @param \stdClass $completion
+     * @return course_completed
+     */
+    public static function create_from_completion(\stdClass $completion) {
+        $event = self::create(
+            array(
+                'objectid' => $completion->id,
+                'relateduserid' => $completion->userid,
+                'context' => \context_course::instance($completion->course),
+                'courseid' => $completion->course,
+                'other' => array('relateduserid' => $completion->userid), // Deprecated since 2.7, please use property relateduserid.
+            )
+        );
+        $event->add_record_snapshot('course_completions', $completion);
+        return $event;
+    }
 
     /**
      * Initialise required event data properties.
@@ -60,7 +85,7 @@ class course_completed extends base {
      * @return string
      */
     public function get_description() {
-        return "The course with the id '$this->courseid' was completed by the user with the id '$this->userid'.";
+        return "The course with the id '$this->courseid' was completed for the user with the id '$this->relateduserid'.";
     }
 
     /**
@@ -89,4 +114,16 @@ class course_completed extends base {
     protected function get_legacy_eventdata() {
         return $this->get_record_snapshot('course_completions', $this->objectid);
     }
+
+    /**
+     * Custom validation.
+     *
+     * @throws \coding_exception
+     * @return void
+     */
+    protected function validate_data() {
+        parent::validate_data();
+
+        // TODO: MDL-45319 add validation of relateduserid and other['relateduserid'].
+    }
 }
diff --git a/mod/quiz/classes/event/attempt_becameoverdue.php b/mod/quiz/classes/event/attempt_becameoverdue.php
index 50ee1154551..945107a8c3c 100644
--- a/mod/quiz/classes/event/attempt_becameoverdue.php
+++ b/mod/quiz/classes/event/attempt_becameoverdue.php
@@ -59,7 +59,7 @@ class attempt_becameoverdue extends \core\event\base {
      * @return string
      */
     public function get_description() {
-
+        return "Attempt with the id '$this->objectid' for the user with the id '$this->relateduserid' became overdue.";
     }
 
     /**
diff --git a/mod/quiz/tests/events_test.php b/mod/quiz/tests/events_test.php
index bad32a0205c..6c70949c2e7 100644
--- a/mod/quiz/tests/events_test.php
+++ b/mod/quiz/tests/events_test.php
@@ -138,6 +138,7 @@ class mod_quiz_events_testcase extends advanced_testcase {
         $this->assertEquals('quiz_attempts', $event->objecttable);
         $this->assertEquals($quizobj->get_context(), $event->get_context());
         $this->assertEquals($attempt->userid, $event->relateduserid);
+        $this->assertNotEmpty($event->get_description());
         // Submitterid should be the user, but as we are in PHP Unit, CLI_SCRIPT is set to true which sets null in submitterid.
         $this->assertEquals(null, $event->other['submitterid']);
         $this->assertEquals('quiz_attempt_overdue', $event->get_legacy_eventname());
diff --git a/mod/workshop/assessment.php b/mod/workshop/assessment.php
index 7a33b104de3..a75b44e8c01 100644
--- a/mod/workshop/assessment.php
+++ b/mod/workshop/assessment.php
@@ -189,7 +189,7 @@ if (is_null($assessment->grade) and !$assessmenteditable) {
         if (count((array)$coredata) > 1 ) {
             $DB->update_record('workshop_assessments', $coredata);
             $params = array(
-                'relateduserid' => $assessment->authorid,
+                'relateduserid' => $submission->authorid,
                 'objectid' => $assessment->id,
                 'context' => $workshop->context,
                 'other' => array(