diff --git a/docs/jsonBrowser/module.md b/docs/jsonBrowser/module.md
index a33f0e0b..44d0a60b 100644
--- a/docs/jsonBrowser/module.md
+++ b/docs/jsonBrowser/module.md
@@ -436,7 +436,7 @@ Property name | Description | Type | Required? | Object reference? | User friend
 pft_method | Indicate which Pulmonary Function Testings (PFTs) methods were performed. Please indicate all tests performed. | array | no |  | Pulmonary Function Testing method | spirometry, plethysmography, DLCO_KCO_test | spirometry; plethysmography; DLCO_KCO_test
 pft_age | Indicate the age of the subject at the time point of Pulmonary Function Testing (PFT) in years, if known. | number | no |  | Age at Pulmonary Function Test |  | 10; 34; 68
 pft_time_point | Indicate at which date the Pulmonary Function Testing (PFT) were recorded as YYYY-MM-DD if available. If this information is not shareable, please indicate 'not_shareable'. | string | no |  | Date at Pulmonary Function Test |  | 2024-11-14; 2019-01-31; not_shareable
-pft_relative_time_point | If timepoint of sample collection (time of collection) and/or timepoint of PFT recording (PFT_time_point) is not available, indicate how many days prior or after sample collection the pulmonary function parameters were assessed if available. | string | no |  | Days between collection and Pulmonary Function Test |  | -5; 2; 0
+pft_relative_time_point | If timepoint of sample collection (time of collection) and/or timepoint of PFT recording (pft_time_point) is not available, indicate how many days prior or after sample collection the pulmonary function parameters were assessed if available. | integer | no |  | Days between collection and Pulmonary Function Test |  | -5; 2; 0
 fev1_predicted | Indicate the predicted Forced Expiratory Volume in 1 second (FEV1) in milliliters, based on patient age, sex, height, and ethnicity, if available. | number | no |  | FEV1 predicted |  | 3500; 4200; 2800
 fev1_prebd | Indicate the measured FEV1 in milliliters before the administration of a bronchodilator if available. | number | no |  | FEV1 before bronchodilator |  | 3000; 3800; 2600
 fev1_postbd | Indicate the measured FEV1 in milliliters after the administration of a bronchodilator if available. | number | no |  | FEV1 after bronchodilator |  | 3200; 4000; 2700
diff --git a/json_schema/module/biomaterial/medical_tests.json b/json_schema/module/biomaterial/medical_tests.json
index d219275f..bad11dce 100644
--- a/json_schema/module/biomaterial/medical_tests.json
+++ b/json_schema/module/biomaterial/medical_tests.json
@@ -50,12 +50,11 @@
         },
         "pft_relative_time_point": {
             "user_friendly": "Days between collection and Pulmonary Function Test",
-            "description": "If timepoint of sample collection (time of collection) and/or timepoint of PFT recording (PFT_time_point) is not available, indicate how many days prior or after sample collection the pulmonary function parameters were assessed if available.",
-            "type": "string",
+            "description": "If timepoint of sample collection (time of collection) and/or timepoint of PFT recording (pft_time_point) is not available, indicate how many days prior or after sample collection the pulmonary function parameters were assessed if available.",
+            "type": "integer",
             "example": "-5; 2; 0",
-            "pattern": "^[\\+\\-]?[0-9]+$",
             "$comment": "pulmonary_function_parameter; lung",
-            "guidelines": "If PFT recording was done before sample collection, then enter a negative day value. If PFT recording was done after sample collection, then enter a positive day value."
+            "guidelines": "If PFT recording was done before sample collection, then enter a negative day value. If PFT recording was done after sample collection, then enter an unsigned positive day value."
 
         },
         "fev1_predicted": {