diff --git a/src/entity/reference_range.ts b/src/entity/reference_range.ts
index 995d6e3..da6a1d3 100644
--- a/src/entity/reference_range.ts
+++ b/src/entity/reference_range.ts
@@ -16,30 +16,34 @@ export class ReferenceRange {
 	gender: Gender;
 
 	@Column({
+		type: 'int',
 		nullable: false,
-		length: 128,
-		default: '0 day',
+		default: 0,
 	})
-	age_range_min: string;
+	age_range_min: number;
 
 	@Column({
+		type: 'int',
 		nullable: false,
-		length: 128,
-		default: '999 years',
+		default: 999,
 	})
-	age_range_max: string;
+	age_range_max: number;
 
 	@Column({
+		type: 'decimal',
+		precision: 10,
+		scale: 2,
 		nullable: false,
-		length: 256,
 	})
-	value_min: string;
+	value_min: number;
 
 	@Column({
+		type: 'decimal',
+		precision: 10,
+		scale: 2,
 		nullable: false,
-		length: 256,
 	})
-	value_max: string;
+	value_max: number;
 
 	@Column({
 		nullable: false,