diff --git a/IRaCIS.Core.Application/Service/Reading/Dto/ReadingMedicineQuestionViewModel.cs b/IRaCIS.Core.Application/Service/Reading/Dto/ReadingMedicineQuestionViewModel.cs
index 75bba26e6..cf0f882b3 100644
--- a/IRaCIS.Core.Application/Service/Reading/Dto/ReadingMedicineQuestionViewModel.cs
+++ b/IRaCIS.Core.Application/Service/Reading/Dto/ReadingMedicineQuestionViewModel.cs
@@ -98,7 +98,7 @@ namespace IRaCIS.Core.Application.ViewModel
 		/// <summary>
 		/// 父问题触发
 		/// </summary>
-		public string ParentTriggerValue { get; set; }
+		public string ParentTriggerValue { get; set; } = string.Empty;
 
 		/// <summary>
 		/// 问题名称
@@ -174,7 +174,7 @@ namespace IRaCIS.Core.Application.ViewModel
 	 		public Guid Id { get; set; }
 	 	
 	 		public string Type { get; set; }
-	 		public string ParentTriggerValue { get; set; }=string.Empty;
+	 		public string? ParentTriggerValue { get; set; }=string.Empty;
 	 		public string QuestionName { get; set; }
 	 		public string TypeValue { get; set; }
 	 		public Guid TrialId { get; set; }