diff --git a/lib/kredis/types/ordered_set.rb b/lib/kredis/types/ordered_set.rb
index 9f68927..6a43ec6 100644
--- a/lib/kredis/types/ordered_set.rb
+++ b/lib/kredis/types/ordered_set.rb
@@ -18,7 +18,7 @@ def remove(*elements)
   end
 
   def include?(element)
-    zrank(type_to_string(element, typed)).present?
+    !!zscore(type_to_string(element, typed))
   end
 
   def prepend(elements)