diff --git a/app/models/champs/checkbox_champ.rb b/app/models/champs/checkbox_champ.rb
index dd8540892..b69e20e02 100644
--- a/app/models/champs/checkbox_champ.rb
+++ b/app/models/champs/checkbox_champ.rb
@@ -1,19 +1,9 @@
-class Champs::CheckboxChamp < Champ
-  def search_terms
-    if value == 'on'
-      [libelle]
-    end
-  end
-
-  def to_s
-    value == 'on' ? 'Oui' : 'Non'
+class Champs::CheckboxChamp < Champs::YesNoChamp
+  def true?
+    value == 'on'
   end
 
   def for_export
-    value == 'on' ? 'on' : 'off'
-  end
-
-  def for_api
-    value == 'on' ? 'on' : 'off'
+    true? ? 'on' : 'off'
   end
 end
diff --git a/app/models/champs/yes_no_champ.rb b/app/models/champs/yes_no_champ.rb
index ca7155b03..4f82a406b 100644
--- a/app/models/champs/yes_no_champ.rb
+++ b/app/models/champs/yes_no_champ.rb
@@ -1,6 +1,6 @@
-class Champs::YesNoChamp < Champs::CheckboxChamp
+class Champs::YesNoChamp < Champ
   def search_terms
-    if value == 'true'
+    if true?
       [libelle]
     end
   end
@@ -13,13 +13,13 @@ class Champs::YesNoChamp < Champs::CheckboxChamp
     processed_value
   end
 
-  def for_api
-    processed_value
+  def true?
+    value == 'true'
   end
 
   private
 
   def processed_value
-    value == 'true' ? 'Oui' : 'Non'
+    true? ? 'Oui' : 'Non'
   end
 end
diff --git a/spec/serializers/champ_serializer_spec.rb b/spec/serializers/champ_serializer_spec.rb
index 7e82150b2..d88916685 100644
--- a/spec/serializers/champ_serializer_spec.rb
+++ b/spec/serializers/champ_serializer_spec.rb
@@ -196,5 +196,65 @@ describe ChampSerializer do
         expect(subject[:entreprise]).to include(capital_social: etablissement.entreprise_capital_social)
       }
     end
+
+    context 'when type champ yes_no' do
+      context 'true' do
+        let(:champ) { create(:champ_yes_no, value: 'true') }
+
+        it { is_expected.to include(value: 'true') }
+      end
+
+      context 'false' do
+        let(:champ) { create(:champ_yes_no, value: 'false') }
+
+        it { is_expected.to include(value: 'false') }
+      end
+
+      context 'nil' do
+        let(:champ) { create(:champ_yes_no, value: nil) }
+
+        it { is_expected.to include(value: nil) }
+      end
+    end
+
+    context 'when type champ checkbox' do
+      context 'on' do
+        let(:champ) { create(:champ_checkbox, value: 'on') }
+
+        it { is_expected.to include(value: 'on') }
+      end
+
+      context 'off' do
+        let(:champ) { create(:champ_checkbox, value: 'off') }
+
+        it { is_expected.to include(value: 'off') }
+      end
+
+      context 'nil' do
+        let(:champ) { create(:champ_checkbox, value: nil) }
+
+        it { is_expected.to include(value: nil) }
+      end
+    end
+
+    context 'when type champ engagement' do
+      context 'on' do
+        let(:champ) { create(:champ_engagement, value: 'on') }
+
+        it { is_expected.to include(value: 'on') }
+      end
+
+      context 'off' do
+        let(:champ) { create(:champ_engagement, value: 'off') }
+
+        it { is_expected.to include(value: 'off') }
+      end
+
+      context 'nil' do
+        let(:champ) { create(:champ_engagement, value: nil) }
+
+        it { is_expected.to include(value: nil) }
+      end
+    end
   end
 end