diff --git a/app/models/diploma.rb b/app/models/diploma.rb
index 787cc8d..d7c7b84 100644
--- a/app/models/diploma.rb
+++ b/app/models/diploma.rb
@@ -60,6 +60,8 @@ class Diploma
       fields_to_show.each do |t|
         if (self.fields[t].type.to_s == "String" || self.fields[t].type.to_s == "Object" rescue false)
           fields_to_remove << t if (datas.where(t.to_sym.ne => nil, t.to_sym.ne => "").count == 0 rescue false)
+        elsif t == "duration"
+          fields_to_remove << t if (datas.where(:start_date.ne => nil).count == 0 rescue false)
         else
           fields_to_remove << t if (datas.where(t.to_sym.ne => nil).count == 0 rescue false)
         end