diff --git a/src/buttons/buttons.js b/src/buttons/buttons.js
index 5650333d58..e895e0d305 100644
--- a/src/buttons/buttons.js
+++ b/src/buttons/buttons.js
@@ -62,9 +62,8 @@ angular.module('ui.bootstrap.buttons', [])
         return getCheckboxValue(attrs.btnCheckboxFalse, false);
       }
 
-      function getCheckboxValue(attributeValue, defaultValue) {
-        var val = scope.$eval(attributeValue);
-        return angular.isDefined(val) ? val : defaultValue;
+      function getCheckboxValue(attribute, defaultValue) {
+        return angular.isDefined(attribute) ? scope.$eval(attribute) : defaultValue;
       }
 
       //model -> UI