diff --git a/src/agenda_culturel/models.py b/src/agenda_culturel/models.py
index 2e150b7..b98dc87 100644
--- a/src/agenda_culturel/models.py
+++ b/src/agenda_culturel/models.py
@@ -628,8 +628,8 @@ class Event(models.Model):
 
     def modified(self):
         return (
-            self.modified_date is None
-            or (self.modified_date - self.created_date).total_seconds() > 1
+            not self.modified_date is None
+            and (self.modified_date - self.created_date).total_seconds() > 1
         )
 
     def nb_draft_events():