diff --git a/platform-operate-api/src/main/java/com/lyms/platform/operate/web/worker/WorkHR.java b/platform-operate-api/src/main/java/com/lyms/platform/operate/web/worker/WorkHR.java
index 72e591a..01673f9 100644
--- a/platform-operate-api/src/main/java/com/lyms/platform/operate/web/worker/WorkHR.java
+++ b/platform-operate-api/src/main/java/com/lyms/platform/operate/web/worker/WorkHR.java
@@ -146,7 +146,7 @@ public class WorkHR implements Callable<List<RiskPatientsResult>> {
 
             riskPatientsResult.setcTimes(i + b);
             riskPatientsResult.setcHTimes(chi + chb);
-            String nextCheckTime = "";
+            String nextCheckTime = null;
 
             if(null!=patients.getNextCheckTime()){
                 nextCheckTime = DateUtil.getyyyy_MM_dd(patients.getNextCheckTime());