diff --git a/Admin/Routes/Web/Backend.php b/Admin/Routes/Web/Backend.php
index 0f5363c..1e8624f 100644
--- a/Admin/Routes/Web/Backend.php
+++ b/Admin/Routes/Web/Backend.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 
 use Modules\Surveys\Controller\BackendController;
 use Modules\Surveys\Models\PermissionState;
diff --git a/Models/Answer.php b/Models/Answer.php
index 878d870..589bf81 100644
--- a/Models/Answer.php
+++ b/Models/Answer.php
@@ -60,16 +60,12 @@ class Answer
         return self::$instances[$id];
     }
 
-    /**
-     * 
-     */
+
     public function init($id) : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function __clone()
     {
     }
@@ -99,37 +95,27 @@ class Answer
         $this->description = $desc;
     }
 
-    /**
-     * 
-     */
+
     public function delete() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function create() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function update() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function serialize() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function unserialize($data) : void
     {
     }
diff --git a/Models/Question.php b/Models/Question.php
index a85ad89..e2ad9f3 100644
--- a/Models/Question.php
+++ b/Models/Question.php
@@ -60,16 +60,12 @@ class Question
         return self::$instances[$id];
     }
 
-    /**
-     * 
-     */
+
     public function init($id) : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function __clone()
     {
     }
@@ -99,37 +95,27 @@ class Question
         $this->description = $desc;
     }
 
-    /**
-     * 
-     */
+
     public function delete() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function create() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function update() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function serialize() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function unserialize($data) : void
     {
     }
diff --git a/Models/Section.php b/Models/Section.php
index 089a492..5837f80 100644
--- a/Models/Section.php
+++ b/Models/Section.php
@@ -85,37 +85,27 @@ class Section
         $this->description = $desc;
     }
 
-    /**
-     * 
-     */
+
     public function delete() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function create() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function update() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function serialize() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function unserialize($data) : void
     {
     }
diff --git a/Models/Survey.php b/Models/Survey.php
index a85a360..5e1a8d9 100644
--- a/Models/Survey.php
+++ b/Models/Survey.php
@@ -76,16 +76,12 @@ class Survey
         return self::$instances[$id];
     }
 
-    /**
-     * 
-     */
+
     public function init($id) : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function __clone()
     {
     }
@@ -135,37 +131,27 @@ class Survey
         $this->creator = $creator;
     }
 
-    /**
-     * 
-     */
+
     public function delete() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function create() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function update() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function serialize() : void
     {
     }
 
-    /**
-     * 
-     */
+
     public function unserialize($data) : void
     {
     }
diff --git a/Theme/Backend/Lang/Navigation.en.lang.php b/Theme/Backend/Lang/Navigation.en.lang.php
index 43bbdcc..f758881 100644
--- a/Theme/Backend/Lang/Navigation.en.lang.php
+++ b/Theme/Backend/Lang/Navigation.en.lang.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 /**
  * Orange Management
  *
diff --git a/Theme/Backend/Lang/api.en.lang.php b/Theme/Backend/Lang/api.en.lang.php
index 959dc12..763b2bb 100644
--- a/Theme/Backend/Lang/api.en.lang.php
+++ b/Theme/Backend/Lang/api.en.lang.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 /**
  * Orange Management
  *
diff --git a/Theme/Backend/Lang/en.lang.php b/Theme/Backend/Lang/en.lang.php
index 1260823..304476d 100644
--- a/Theme/Backend/Lang/en.lang.php
+++ b/Theme/Backend/Lang/en.lang.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 /**
  * Orange Management
  *
diff --git a/Theme/Backend/surveys-create.tpl.php b/Theme/Backend/surveys-create.tpl.php
index ba3b1d4..65599df 100644
--- a/Theme/Backend/surveys-create.tpl.php
+++ b/Theme/Backend/surveys-create.tpl.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 /**
  * Orange Management
  *
diff --git a/Theme/Backend/surveys-list.tpl.php b/Theme/Backend/surveys-list.tpl.php
index a23a589..9399df8 100644
--- a/Theme/Backend/surveys-list.tpl.php
+++ b/Theme/Backend/surveys-list.tpl.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 /**
  * Orange Management
  *
diff --git a/Theme/Backend/surveys-profile.tpl.php b/Theme/Backend/surveys-profile.tpl.php
index 12be972..0bb3664 100644
--- a/Theme/Backend/surveys-profile.tpl.php
+++ b/Theme/Backend/surveys-profile.tpl.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(strict_types=1);
 /**
  * Orange Management
  *
@@ -11,4 +11,3 @@
  * @link       http://website.orange-management.de
  */
 echo $this->getData('nav')->render();
-