diff --git a/longs/forms.py b/longs/forms.py
index 2bc89dce..448c5565 100755
--- a/longs/forms.py
+++ b/longs/forms.py
@@ -74,7 +74,7 @@ class LongSeriesForm(ModelForm):
 
     def __init__(self, *args, **kwargs):
         super(LongSeriesForm, self).__init__(*args, **kwargs)
-        self.fields["examination"] = ModelChoiceField(
+        self.fields["examination"] = ChoiceField(
             queryset=Examination.objects.all(),
             widget=FilteredSelectMultiple(verbose_name="Examination", is_stacked=False),
         )