diff --git a/IRaCIS.Core.Application/Service/Stat/StatisticsService.cs b/IRaCIS.Core.Application/Service/Stat/StatisticsService.cs
index 2fbe880e8..f662d038d 100644
--- a/IRaCIS.Core.Application/Service/Stat/StatisticsService.cs
+++ b/IRaCIS.Core.Application/Service/Stat/StatisticsService.cs
@@ -813,7 +813,7 @@ namespace IRaCIS.Core.Application.Service
                                    LastName = doctorItem.LastName,
                                    ChineseName = doctorItem.ChineseName,
 
-                                   TrialCode = trialItem.TrialCode
+                                   TrialCode = trialItem==null?"": trialItem.TrialCode
                                };
             return reviewerList.ToList();