diff --git a/tests/test_model_serializer.py b/tests/test_model_serializer.py
index 7b07b5237..f2f053bf0 100644
--- a/tests/test_model_serializer.py
+++ b/tests/test_model_serializer.py
@@ -978,4 +978,4 @@ class TestSerializerDefaultTrueBoolean(TestCase):
         data.update({'required_data': 'foo'})
         serializer = self.default_true_boolean_serializer(data=data)
         serializer.is_valid()
-        self.assertTrue(serializer.data['visible'])
+        self.assertNotIn('visible', serializer.validated_data)