diff --git a/php/libraries/Utility.class.inc b/php/libraries/Utility.class.inc
index f6beac25bab..3e88437822d 100644
--- a/php/libraries/Utility.class.inc
+++ b/php/libraries/Utility.class.inc
@@ -715,7 +715,9 @@ class Utility
             );
         } elseif (!is_null($commentID)) { //get sourcefield using commentid
             $instrument   = $DB->pselectOne(
-                "SELECT Test_name FROM flag WHERE CommentID = :cid",
+                "SELECT Test_name FROM flag
+                 JOIN test_names ON (test_names.ID = flag.TestID)
+                 WHERE CommentID = :cid",
                 ['cid' => $commentID]
             );
             $sourcefields = $DB->pselect(
diff --git a/tools/data_integrity/data_deletion/delete_timepoint.php b/tools/data_integrity/data_deletion/delete_timepoint.php
index 7f4abae3899..aeb9023a16b 100755
--- a/tools/data_integrity/data_deletion/delete_timepoint.php
+++ b/tools/data_integrity/data_deletion/delete_timepoint.php
@@ -180,7 +180,10 @@ function deleteTimepoint(
     echo "\n###############################################################\n";
 
     $instruments = $DB->pselect(
-        'SELECT Test_name, CommentID FROM flag WHERE SessionID=:sid',
+        'SELECT Test_name, CommentID
+         FROM flag
+         JOIN test_names ON (test_names.ID = flag.TestID)
+         WHERE SessionID=:sid',
         ['sid' => $sessionID]
     );
 
diff --git a/tools/data_integrity_check.php b/tools/data_integrity_check.php
index 513b356833b..730e93f3678 100644
--- a/tools/data_integrity_check.php
+++ b/tools/data_integrity_check.php
@@ -37,6 +37,10 @@
             {$instrument}
         ON
             {$instrument}.CommentID = flag.CommentID
+        LEFT JOIN
+            test_names
+        ON
+            (test_names.ID = flag.TestID)
         WHERE
             Test_name = :instrument AND
             {$instrument}.CommentID IS NULL
@@ -80,6 +84,10 @@
         SessionID,Test_name,CommentID
     FROM
         flag
+    JOIN
+        test_names
+    ON
+        (test_names.ID = flag.TestID)
     WHERE
         (
             flag.CommentID NOT LIKE 'DDE_%' AND
@@ -88,10 +96,14 @@
                     COUNT(*)
                 FROM
                     flag test
+                JOIN
+                    test_names
+                ON
+                    (test_names.ID = flag.TestID)
                 WHERE
                     test.CommentID NOT LIKE 'DDE_%' AND
                     flag.SessionID = test.SessionID AND
-                    flag.Test_name = test.Test_name
+                    test_names.Test_name = test.Test_name
             ) > 1
         ) OR
         (
@@ -101,10 +113,14 @@
                     COUNT(*)
                 FROM
                     flag test
+                JOIN
+                    test_names
+                ON
+                    (test_names.ID = flag.TestID)
                 WHERE
                     test.CommentID LIKE 'DDE_%' AND
                     flag.SessionID = test.SessionID AND
-                    flag.Test_name = test.Test_name
+                    test_names.Test_name = test.Test_name
             ) > 1
         )
 ",
diff --git a/tools/fix_timepoint_date_problems.php b/tools/fix_timepoint_date_problems.php
index 6567ae95a87..49178b196ab 100755
--- a/tools/fix_timepoint_date_problems.php
+++ b/tools/fix_timepoint_date_problems.php
@@ -428,7 +428,9 @@ function addInstrument($sessionID, $testName, $loris)
 
     // get CommentID of the newly assigned instrument
     $query = "SELECT CommentID FROM flag
-        WHERE SessionID='$sessionID' AND Test_name='$testName'";
+              JOIN test_names ON (test_names.ID = flag.TestID)
+              WHERE SessionID='$sessionID'
+              AND Test_name='$testName'";
 
     /*
      * add Feedback