diff --git a/gdcdictionary/schemas/case.yaml b/gdcdictionary/schemas/case.yaml
index f58bd008..c3801928 100644
--- a/gdcdictionary/schemas/case.yaml
+++ b/gdcdictionary/schemas/case.yaml
@@ -31,7 +31,7 @@ links:
 required:
   - submitter_id
   - type
-  - index_date
+  - index_event
   - studies
 
 uniqueKeys: