diff --git a/docs/explanations/curator_data_model.md b/docs/explanations/curator_data_model.md
index 6dd6fea5b..9cffaca61 100644
--- a/docs/explanations/curator_data_model.md
+++ b/docs/explanations/curator_data_model.md
@@ -412,7 +412,8 @@ As a result of the above data model, in the JSON Schema:
               "Cancer"
             ]
           }
-        }
+        },
+        "required": ["Diagnosis"]
       },
       "then": {
         "required": ["Cancer Type", "Family History"]