diff --git a/StandardizedClinicalDataTables/SPECIMEN.md b/StandardizedClinicalDataTables/SPECIMEN.md
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--- a/StandardizedClinicalDataTables/SPECIMEN.md
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-#specimen
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+The specimen domain contains the records identifying biological samples from a person.
+ 
+Field|Required|Type|Description
+:----|:----|:-----|:-----
+|specimen_id|Yes|integer|A unique identifier for each specimen.|
+|person_id|Yes|integer|A foreign key identifier to the Person for whom the Specimen is recorded.|
+|specimen_concept_id|Yes|integer|A foreign key referring to a Standard Concept identifier in the Standardized Vocabularies for the Specimen.|
+|specimen_type_concept_id|Yes|integer|A foreign key referring to the Concept identifier in the Standardized Vocabularies reflecting the system of record from which the Specimen was represented in the source data.|
+|specimen_date|Yes|date|The date the specimen was obtained from the Person.|
+|specimen_datetime|No|datetime|The date and time on the date when the Specimen was obtained from the person.|
+|quantity|No|float|The amount of specimen collection from the person during the sampling procedure.|
+|unit_concept_id|No|integer|A foreign key to a Standard Concept identifier for the Unit associated with the numeric quantity of the Specimen collection.|
+|anatomic_site_concept_id|No|integer|A foreign key to a Standard Concept identifier for the anatomic location of specimen collection.|
+|disease_status_concept_id|No|integer|A foreign key to a Standard Concept identifier for the Disease Status of specimen collection.|
+|specimen_source_id|No|varchar(50)|The Specimen identifier as it appears in the source data.|
+|specimen_source_value|No|varchar(50)|The Specimen value as it appears in the source data. This value is mapped to a Standard Concept in the Standardized Vocabularies and the original code is, stored here for reference.|
+|unit_source_value|No|varchar(50)|The information about the Unit as detailed in the source.|
+|anatomic_site_source_value|No|varchar(50)|The information about the anatomic site as detailed in the source.|
+|disease_status_source_value|No|varchar(50)|The information about the disease status as detailed in the source.|
+
+### Conventions 
+  * Anatomic site is coded at the most specific level of granularity possible, such that higher level classifications can be derived using the Standardized Vocabularies.
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