diff --git a/src/EnvironmentCheckSuite.php b/src/EnvironmentCheckSuite.php
index 2cf0afb..57fa633 100644
--- a/src/EnvironmentCheckSuite.php
+++ b/src/EnvironmentCheckSuite.php
@@ -109,6 +109,7 @@ class EnvironmentCheckSuite
 
         foreach ($this->checkInstances() as $check) {
             list($checkClass, $checkTitle) = $check;
+            $responseTime = 'Not Found';
             try {
                 $startTime = microtime(true);
                 list($status, $message) = $checkClass->check();
diff --git a/src/EnvironmentCheckSuiteResult.php b/src/EnvironmentCheckSuiteResult.php
index 8a023c8..2cd1c3a 100644
--- a/src/EnvironmentCheckSuiteResult.php
+++ b/src/EnvironmentCheckSuiteResult.php
@@ -34,8 +34,9 @@ class EnvironmentCheckSuiteResult extends ViewableData
      * @param int $status
      * @param string $message
      * @param string $checkIdentifier
+     * @param string $responseTime
      */
-    public function addResult($status, $message, $checkIdentifier, $responseTime)
+    public function addResult($status, $message, $checkIdentifier, $responseTime = null)
     {
         $this->details->push(new ArrayData([
             'Check' => $checkIdentifier,