diff --git a/client/src/store/index.ts b/client/src/store/index.ts
index 6065159d..94216a81 100644
--- a/client/src/store/index.ts
+++ b/client/src/store/index.ts
@@ -336,7 +336,7 @@ const {
         forwardTo: currentFrame.nextFrame,
         upTo: currentFrame.firstFrameInPreviousScan,
         downTo: currentFrame.firstFrameInNextScan,
-        currentAutoEvaluation: currentFrame.auto_evaluation,
+        currentAutoEvaluation: currentFrame.frame_evaluation,
         autoWindow: experiment.autoWindow,
         autoLevel: experiment.autoLevel,
       };
diff --git a/miqa/core/migrations/0019_unique_evaluation.py b/miqa/core/migrations/0019_unique_evaluation.py
new file mode 100644
index 00000000..8ce7b0fe
--- /dev/null
+++ b/miqa/core/migrations/0019_unique_evaluation.py
@@ -0,0 +1,23 @@
+# Generated by Django 3.2.8 on 2021-11-06 16:46
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0018_image_to_frame'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='evaluation',
+            name='frame',
+            field=models.OneToOneField(
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name='frame_evaluation',
+                to='core.frame',
+            ),
+        ),
+    ]
diff --git a/miqa/core/models/evaluation.py b/miqa/core/models/evaluation.py
index a4609133..a6790322 100644
--- a/miqa/core/models/evaluation.py
+++ b/miqa/core/models/evaluation.py
@@ -5,7 +5,11 @@
 
 class Evaluation(models.Model):
     id = models.UUIDField(primary_key=True, default=uuid4, editable=False)
-    frame = models.ForeignKey('Frame', null=False, on_delete=models.PROTECT)
+    frame = models.OneToOneField(
+        'Frame',
+        on_delete=models.CASCADE,
+        related_name='frame_evaluation',
+    )
     evaluation_model = models.CharField(max_length=50)
     results = models.JSONField()
 
diff --git a/miqa/core/rest/frame.py b/miqa/core/rest/frame.py
index e55aa91e..8770a1cf 100644
--- a/miqa/core/rest/frame.py
+++ b/miqa/core/rest/frame.py
@@ -22,17 +22,10 @@ class Meta:
 class FrameSerializer(serializers.ModelSerializer):
     class Meta:
         model = Frame
-        fields = ['id', 'frame_number', 'auto_evaluation']
+        fields = ['id', 'frame_number', 'frame_evaluation']
         ref_name = 'scan_frame'
 
-    auto_evaluation = serializers.SerializerMethodField()
-
-    def get_auto_evaluation(self, frame_object):
-        try:
-            evaluation_object = Evaluation.objects.get(frame=frame_object)
-            return EvaluationSerializer(evaluation_object).data
-        except Evaluation.DoesNotExist:
-            return None
+    frame_evaluation = EvaluationSerializer()
 
 
 class FrameViewSet(ListModelMixin, GenericViewSet):