diff --git a/force_bdss/core/data_value.py b/force_bdss/core/data_value.py
index fc20a499dea0dc3002d660402090f44b1c797cd9..f360446aa6bfd6956064be9097cb3a541a869dd0 100644
--- a/force_bdss/core/data_value.py
+++ b/force_bdss/core/data_value.py
@@ -1,4 +1,4 @@
-from traits.api import HasStrictTraits, Any, String, Int
+from traits.api import HasStrictTraits, Any, String, Int, Enum
 
 
 class DataValue(HasStrictTraits):
@@ -16,9 +16,11 @@ class DataValue(HasStrictTraits):
     #: The value.
     value = Any()
 
+    # The numerical accuracy of the value.
     accuracy = Any()
 
-    quality = Int()
+    #: A flag for the quality of the data.
+    quality = Enum("AVERAGE", "POOR", "GOOD")
 
     def __str__(self):
         return """
diff --git a/force_bdss/core/tests/__init__.py b/force_bdss/core/tests/__init__.py
new file mode 100644
index 0000000000000000000000000000000000000000..e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
diff --git a/force_bdss/core/tests/test_data_value.py b/force_bdss/core/tests/test_data_value.py
new file mode 100644
index 0000000000000000000000000000000000000000..c4aa5490a63ba709a442f8c46eafd867c326eb78
--- /dev/null
+++ b/force_bdss/core/tests/test_data_value.py
@@ -0,0 +1,13 @@
+import unittest
+
+from force_bdss.core.data_value import DataValue
+
+
+class TestDataValue(unittest.TestCase):
+    def test_initialization(self):
+        dv = DataValue()
+        self.assertEqual(dv.type, "")
+        self.assertEqual(dv.value, None)
+        self.assertEqual(dv.accuracy, None)
+        self.assertEqual(dv.quality, "AVERAGE")
+