diff --git a/mimic-iv/concepts/comorbidity/charlson.sql b/mimic-iv/concepts/comorbidity/charlson.sql
index 15911b37b..3a8891f60 100644
--- a/mimic-iv/concepts/comorbidity/charlson.sql
+++ b/mimic-iv/concepts/comorbidity/charlson.sql
@@ -350,10 +350,10 @@ WITH diag AS (
     SELECT
         hadm_id
         , age
-        , CASE WHEN age <= 50 THEN 0
-            WHEN age <= 60 THEN 1
-            WHEN age <= 70 THEN 2
-            WHEN age <= 80 THEN 3
+        , CASE WHEN age < 50 THEN 0
+            WHEN age < 60 THEN 1
+            WHEN age < 70 THEN 2
+            WHEN age < 80 THEN 3
             ELSE 4 END AS age_score
     FROM `physionet-data.mimiciv_derived.age`
 )
diff --git a/mimic-iv/concepts_duckdb/comorbidity/charlson.sql b/mimic-iv/concepts_duckdb/comorbidity/charlson.sql
index be191aa82..e89283e0b 100644
--- a/mimic-iv/concepts_duckdb/comorbidity/charlson.sql
+++ b/mimic-iv/concepts_duckdb/comorbidity/charlson.sql
@@ -330,13 +330,13 @@ WITH diag AS (
     hadm_id,
     age,
     CASE
-      WHEN age <= 50
+      WHEN age < 50
       THEN 0
-      WHEN age <= 60
+      WHEN age < 60
       THEN 1
-      WHEN age <= 70
+      WHEN age < 70
       THEN 2
-      WHEN age <= 80
+      WHEN age < 80
       THEN 3
       ELSE 4
     END AS age_score
diff --git a/mimic-iv/concepts_postgres/comorbidity/charlson.sql b/mimic-iv/concepts_postgres/comorbidity/charlson.sql
index 1655dba02..45920cede 100644
--- a/mimic-iv/concepts_postgres/comorbidity/charlson.sql
+++ b/mimic-iv/concepts_postgres/comorbidity/charlson.sql
@@ -331,13 +331,13 @@ WITH diag AS (
     hadm_id,
     age,
     CASE
-      WHEN age <= 50
+      WHEN age < 50
       THEN 0
-      WHEN age <= 60
+      WHEN age < 60
       THEN 1
-      WHEN age <= 70
+      WHEN age < 70
       THEN 2
-      WHEN age <= 80
+      WHEN age < 80
       THEN 3
       ELSE 4
     END AS age_score