diff --git a/app/models/site.rb b/app/models/site.rb
index ce0a7c4..aaa88e0 100644
--- a/app/models/site.rb
+++ b/app/models/site.rb
@@ -187,6 +187,7 @@ class Site
   end
 
   def invitadxs
+    return [] unless invitadxs?
     @invitadxs ||= File.read(invitadxs_file).split("\n").map do |i|
       Invitadx.find_by_email(i)
     end