postgres.omop contains 391 columns - click on heading to sort:

Table	Column	Type	Size	Nulls	Auto	Default	Comments
attribute_definition	attribute_definition_id	int4	10				A unique identifier for each Attribute.
attribute_definition	attribute_description	text	2147483647	√		null	A complete description of the Attribute definition
attribute_definition	attribute_name	varchar	255				A short description of the Attribute.
attribute_definition	attribute_syntax	text	2147483647	√		null	Syntax or code to operationalize the Attribute definition
attribute_definition	attribute_type_concept_id	int4	10				Type defining what kind of Attribute Definition the record represents and how the syntax may be executed
care_site	care_site_id	int4	10				A unique identifier for each Care Site.
care_site	care_site_name	varchar	255	√		null	The verbatim description or name of the Care Site as in data source
care_site	care_site_source_value	varchar	50	√		null	The identifier for the Care Site in the source data, stored here for reference.
care_site	location_id	int4	10	√		null	A foreign key to the geographic Location in the LOCATION table, where the detailed address information is stored.
care_site	place_of_service_concept_id	int4	10	√		null	A foreign key that refers to a Place of Service Concept ID in the Standardized Vocabularies.
care_site	place_of_service_source_value	varchar	50	√		null	The source code for the Place of Service as it appears in the source data, stored here for reference.
cdm_source	cdm_etl_reference	varchar	255	√		null	URL or other external reference to location of ETL specification documentation and ETL source code
cdm_source	cdm_holder	varchar	255	√		null	The name of the organization responsible for the development of the CDM instance
cdm_source	cdm_release_date	date	13	√		null	The date when the CDM was instantiated
cdm_source	cdm_source_abbreviation	varchar	25	√		null	An abbreviation of the name
cdm_source	cdm_source_name	varchar	255				The full name of the source
cdm_source	cdm_version	varchar	10	√		null	The version of CDM used
cdm_source	source_description	text	2147483647	√		null	A description of the source data origin and purpose for collection. The description may contain a summary of the period of time that is expected to be covered by this dataset.
cdm_source	source_documentation_reference	varchar	255	√		null	URL or other external reference to location of source documentation
cdm_source	source_release_date	date	13	√		null	The date for which the source data are most current, such as the last day of data capture
cdm_source	vocabulary_version	varchar	20	√		null	The version of the vocabulary used
cohort	cohort_definition_id	int4	10				A foreign key to a record in the COHORT_DEFINITION table containing relevant Cohort Definition information.
cohort	cohort_end_date	date	13				The date when the Cohort Definition criteria for the Person, Provider or Visit no longer match or the Cohort membership was terminated.
cohort	cohort_start_date	date	13				The date when the Cohort Definition criteria for the Person, Provider or Visit first match.
cohort	subject_id	int4	10				A foreign key to the subject in the cohort. These could be referring to records in the PERSON, PROVIDER, VISIT_OCCURRENCE table.
cohort_attribute	attribute_definition_id	int4	10				A foreign key to a record in the [ATTRIBUTE_DEFINITION](https://github.com/OHDSI/CommonDataModel/wiki/ATTRIBUTE_DEFINITION) table containing relevant Attribute Definition information.
cohort_attribute	cohort_definition_id	int4	10				A foreign key to a record in the [COHORT_DEFINITION](https://github.com/OHDSI/CommonDataModel/wiki/COHORT_DEFINITION) table containing relevant Cohort Definition information.
cohort_attribute	cohort_end_date	date	13				The date when the Cohort Definition criteria for the Person, Provider or Visit no longer match or the Cohort membership was terminated.
cohort_attribute	cohort_start_date	date	13				The date when the Cohort Definition criteria for the Person, Provider or Visit first match.
cohort_attribute	subject_id	int4	10				A foreign key to the subject in the Cohort. These could be referring to records in the PERSON, PROVIDER, VISIT_OCCURRENCE table.
cohort_attribute	value_as_concept_id	int4	10	√		null	The attribute result stored as a Concept ID. This is applicable to attributes where the result is expressed as a categorical value.
cohort_attribute	value_as_number	numeric	131089	√		null	The attribute result stored as a number. This is applicable to attributes where the result is expressed as a numeric value.
cohort_definition	cohort_definition_description	text	2147483647	√		null	A complete description of the Cohort definition
cohort_definition	cohort_definition_id	int4	10				A unique identifier for each Cohort.
cohort_definition	cohort_definition_name	varchar	255				A short description of the Cohort.
cohort_definition	cohort_definition_syntax	text	2147483647	√		null	Syntax or code to operationalize the Cohort definition
cohort_definition	cohort_initiation_date	date	13	√		null	A date to indicate when the Cohort was initiated in the COHORT table
cohort_definition	definition_type_concept_id	int4	10				Type defining what kind of Cohort Definition the record represents and how the syntax may be executed
cohort_definition	subject_concept_id	int4	10				A foreign key to the Concept to which defines the domain of subjects that are members of the cohort (e.g., Person, Provider, Visit).
concept	concept_class_id	varchar	20				The attribute or concept class of the Concept. Examples are 'Clinical Drug', 'Ingredient', 'Clinical Finding'etc.
concept	concept_code	varchar	50				The concept code represents the identifier of the Concept in the source vocabulary, such as SNOMED-CT concept IDs, RxNorm RXCUIs etc. Note that concept codes are not unique across vocabularies.
concept	concept_id	int4	10				A unique identifier for each Concept across all domains.
concept	concept_name	varchar	255				An unambiguous, meaningful and descriptive name for the Concept.
concept	domain_id	varchar	20				A foreign key to the [DOMAIN](https://github.com/OHDSI/CommonDataModel/wiki/DOMAIN) table the Concept belongs to.
concept	invalid_reason	varchar	1	√		null	Reason the Concept was invalidated. Possible values are D (deleted), U (replaced with an update) or NULL when valid_end_date has the default value.
concept	standard_concept	varchar	1	√		null	This flag determines where a Concept is a Standard Concept, i.e. is used in the data, a Classification Concept, or a non-standard Source Concept. The allowables values are 'S'(Standard Concept) and 'C'(Classification Concept), otherwise the content is NULL.
concept	valid_end_date	date	13				The date when the Concept became invalid because it was deleted or superseded (updated) by a new concept. The default value is 31-Dec-2099, meaning, the Concept is valid until it becomes deprecated.
concept	valid_start_date	date	13				The date when the Concept was first recorded. The default value is 1-Jan-1970, meaning, the Concept has no (known) date of inception.
concept	vocabulary_id	varchar	20				A foreign key to the [VOCABULARY](https://github.com/OHDSI/CommonDataModel/wiki/VOCABULARY) table indicating from which source the Concept has been adapted.
concept_ancestor	ancestor_concept_id	int4	10				A foreign key to the concept in the concept table for the higher-level concept that forms the ancestor in the relationship.
concept_ancestor	descendant_concept_id	int4	10				A foreign key to the concept in the concept table for the lower-level concept that forms the descendant in the relationship.
concept_ancestor	max_levels_of_separation	int4	10				The maximum separation in number of levels of hierarchy between ancestor and descendant concepts. This is an attribute that is used to simplify hierarchic analysis.
concept_ancestor	min_levels_of_separation	int4	10				The minimum separation in number of levels of hierarchy between ancestor and descendant concepts. This is an attribute that is used to simplify hierarchic analysis.
concept_class	concept_class_concept_id	int4	10				A foreign key that refers to an identifier in the [CONCEPT](https://github.com/OHDSI/CommonDataModel/wiki/CONCEPT) table for the unique Concept Class the record belongs to.
concept_class	concept_class_id	varchar	20				A unique key for each class.
concept_class	concept_class_name	varchar	255				The name describing the Concept Class, e.g. "Clinical Finding", "Ingredient", etc.
concept_relationship	concept_id_1	int4	10				A foreign key to a Concept in the [CONCEPT](https://github.com/OHDSI/CommonDataModel/wiki/CONCEPT) table associated with the relationship. Relationships are directional, and this field represents the source concept designation.
concept_relationship	concept_id_2	int4	10				A foreign key to a Concept in the [CONCEPT](https://github.com/OHDSI/CommonDataModel/wiki/CONCEPT) table associated with the relationship. Relationships are directional, and this field represents the destination concept designation.
concept_relationship	invalid_reason	varchar	1	√		null	Reason the relationship was invalidated. Possible values are 'D'(deleted), 'U'(replaced with an update) or NULL when valid_end_date has the default value.
concept_relationship	relationship_id	varchar	20				A unique identifier to the type or nature of the Relationship as defined in the [RELATIONSHIP](https://github.com/OHDSI/CommonDataModel/wiki/RELATIONSHIP) table.
concept_relationship	valid_end_date	date	13				The date when the Concept Relationship became invalid because it was deleted or superseded (updated) by a new relationship. Default value is 31-Dec-2099.
concept_relationship	valid_start_date	date	13				The date when the instance of the Concept Relationship is first recorded.
concept_synonym	concept_id	int4	10				A foreign key to the Concept in the CONCEPT table.
concept_synonym	concept_synonym_name	varchar	1000				The alternative name for the Concept.
concept_synonym	language_concept_id	int4	10				A foreign key to a Concept representing the language.
condition_era	condition_concept_id	int4	10				A foreign key that refers to a standard Condition Concept identifier in the Standardized Vocabularies.
condition_era	condition_era_end_date	date	13				The end date for the Condition Era constructed from the individual instances of Condition Occurrences. It is the end date of the final continuously recorded instance of the Condition.
condition_era	condition_era_id	int4	10				A unique identifier for each Condition Era.
condition_era	condition_era_start_date	date	13				The start date for the Condition Era constructed from the individual instances of Condition Occurrences. It is the start date of the very first chronologically recorded instance of the condition.
condition_era	condition_occurrence_count	int4	10	√		null	The number of individual Condition Occurrences used to construct the condition era.
condition_era	person_id	int4	10				A foreign key identifier to the Person who is experiencing the Condition during the Condition Era. The demographic details of that Person are stored in the PERSON table.
condition_occurrence	condition_concept_id	int4	10				A foreign key that refers to a Standard Condition Concept identifier in the Standardized Vocabularies.
condition_occurrence	condition_end_date	date	13	√		null	The date when the instance of the Condition is considered to have ended.
condition_occurrence	condition_end_datetime	timestamp	29,6	√		null	The date when the instance of the Condition is considered to have ended.
condition_occurrence	condition_occurrence_id	int4	10				A unique identifier for each Condition Occurrence event.
condition_occurrence	condition_source_concept_id	int4	10	√		null	A foreign key to a Condition Concept that refers to the code used in the source.
condition_occurrence	condition_source_value	varchar	50	√		null	The source code for the condition as it appears in the source data. This code is mapped to a standard condition concept in the Standardized Vocabularies and the original code is stored here for reference.
condition_occurrence	condition_start_date	date	13				The date when the instance of the Condition is recorded.
condition_occurrence	condition_start_datetime	timestamp	29,6				The date and time when the instance of the Condition is recorded.
condition_occurrence	condition_status_concept_id	int4	10	√		null	A foreign key to the predefined concept in the standard vocabulary reflecting the condition status
condition_occurrence	condition_status_source_value	varchar	50	√		null	The source code for the condition status as it appears in the source data.
condition_occurrence	condition_type_concept_id	int4	10				A foreign key to the predefined Concept identifier in the Standardized Vocabularies reflecting the source data from which the condition was recorded, the level of standardization, and the type of occurrence.
condition_occurrence	person_id	int4	10				A foreign key identifier to the Person who is experiencing the condition. The demographic details of that Person are stored in the PERSON table.
condition_occurrence	provider_id	int4	10	√		null	A foreign key to the Provider in the PROVIDER table who was responsible for capturing (diagnosing) the Condition.
condition_occurrence	stop_reason	varchar	20	√		null	The reason that the condition was no longer present, as indicated in the source data.
condition_occurrence	visit_detail_id	int4	10	√		null	A foreign key to the visit in the VISIT_DETAIL table during which the Condition was determined (diagnosed).
condition_occurrence	visit_occurrence_id	int4	10	√		null	A foreign key to the visit in the VISIT_OCCURRENCE table during which the Condition was determined (diagnosed).
cost	amount_allowed	numeric	131089	√		null	The contracted amount agreed between the payer and provider.
cost	cost_domain_id	varchar	20				The concept representing the domain of the cost event, from which the corresponding table can be inferred that contains the entity for which cost information is recorded.
cost	cost_event_id	int4	10				A foreign key identifier to the event (e.g. Measurement, Procedure, Visit, Drug Exposure, etc) record for which cost data are recorded.
cost	cost_id	int4	10				A unique identifier for each COST record.
cost	cost_type_concept_id	int4	10				A foreign key identifier to a concept in the CONCEPT table for the provenance or the source of the COST data: Calculated from insurance claim information, provider revenue, calculated from cost-to-charge ratio, reported from accounting database, etc.
cost	currency_concept_id	int4	10	√		null	A foreign key identifier to the concept representing the 3-letter code used to delineate international currencies, such as USD for US Dollar.
cost	drg_concept_id	int4	10	√		null	A foreign key to the predefined concept in the DRG Vocabulary reflecting the DRG for a visit.
cost	drg_source_value	varchar	3	√		null	The 3-digit DRG source code as it appears in the source data.
cost	paid_by_patient	numeric	131089	√		null	The total amount paid by the Person as a share of the expenses.
cost	paid_by_payer	numeric	131089	√		null	The amount paid by the Payer for the goods or services.
cost	paid_by_primary	numeric	131089	√		null	The amount paid by a primary Payer through the coordination of benefits.
cost	paid_dispensing_fee	numeric	131089	√		null	The amount paid by the Payer to a pharmacy for dispensing a drug, excluding the amount paid for the drug ingredient. paid_dispensing_fee contributes to the paid_by_payer field if this field is populated with a nonzero value.
cost	paid_ingredient_cost	numeric	131089	√		null	The amount paid by the Payer to a pharmacy for the drug, excluding the amount paid for dispensing the drug. paid_ingredient_cost contributes to the paid_by_payer field if this field is populated with a nonzero value.
cost	paid_patient_coinsurance	numeric	131089	√		null	The amount paid by the Person as a joint assumption of risk. Typically, this is a percentage of the expenses defined by the Payer Plan after the Person's deductible is exceeded.
cost	paid_patient_copay	numeric	131089	√		null	The amount paid by the Person as a fixed contribution to the expenses.
cost	paid_patient_deductible	numeric	131089	√		null	The amount paid by the Person that is counted toward the deductible defined by the Payer Plan. paid_patient_deductible does contribute to the paid_by_patient variable.
cost	payer_plan_period_id	int4	10	√		null	A foreign key to the PAYER_PLAN_PERIOD table, where the details of the Payer, Plan and Family are stored. Record the payer_plan_id that relates to the payer who contributed to the paid_by_payer field.
cost	revenue_code_concept_id	int4	10	√		null	A foreign key referring to a Standard Concept ID in the Standardized Vocabularies for Revenue codes.
cost	revenue_code_source_value	varchar	50	√		null	The source code for the Revenue code as it appears in the source data, stored here for reference.
cost	total_charge	numeric	131089	√		null	The total amount charged by some provider of goods or services (e.g. hospital, physician pharmacy, dme provider) to payers (insurance companies, the patient).
cost	total_cost	numeric	131089	√		null	The cost incurred by the provider of goods or services.
cost	total_paid	numeric	131089	√		null	The total amount actually paid from all payers for goods or services of the provider.
death	cause_concept_id	int4	10	√		null	A foreign key referring to a standard concept identifier in the Standardized Vocabularies for conditions.
death	cause_source_concept_id	int4	10	√		null	A foreign key to the concept that refers to the code used in the source. Note, this variable name is abbreviated to ensure it will be allowable across database platforms.
death	cause_source_value	varchar	50	√		null	The source code for the cause of death as it appears in the source data. This code is mapped to a standard concept in the Standardized Vocabularies and the original code is, stored here for reference.
death	death_date	date	13				The date the person was deceased. If the precise date including day or month is not known or not allowed, December is used as the default month, and the last day of the month the default day.
death	death_datetime	timestamp	29,6	√		null	The date and time the person was deceased. If the precise date including day or month is not known or not allowed, December is used as the default month, and the last day of the month the default day.
death	death_type_concept_id	int4	10				A foreign key referring to the predefined concept identifier in the Standardized Vocabularies reflecting how the death was represented in the source data.
death	person_id	int4	10				A foreign key identifier to the deceased person. The demographic details of that person are stored in the person table.
device_exposure	device_concept_id	int4	10				A foreign key that refers to a Standard Concept identifier in the Standardized Vocabularies for the Device concept.
device_exposure	device_exposure_end_date	date	13	√		null	The date the Device or supply was removed from use.
device_exposure	device_exposure_end_datetime	timestamp	29,6	√		null	The date and time the Device or supply was removed from use.
device_exposure	device_exposure_id	int4	10				A system-generated unique identifier for each Device Exposure.
device_exposure	device_exposure_start_date	date	13				The date the Device or supply was applied or used.
device_exposure	device_exposure_start_datetime	timestamp	29,6				The date and time the Device or supply was applied or used.
device_exposure	device_source_concept_id	int4	10	√		null	A foreign key to a Device Concept that refers to the code used in the source.
device_exposure	device_source_value	varchar	100	√		null	The source code for the Device as it appears in the source data. This code is mapped to a standard Device Concept in the Standardized Vocabularies and the original code is stored here for reference.
device_exposure	device_type_concept_id	int4	10				A foreign key to the predefined Concept identifier in the Standardized Vocabularies reflecting the type of Device Exposure recorded. It indicates how the Device Exposure was represented in the source data.
device_exposure	person_id	int4	10				A foreign key identifier to the Person who is subjected to the Device. The demographic details of that person are stored in the Person table.
device_exposure	provider_id	int4	10	√		null	A foreign key to the provider in the PROVIDER table who initiated of administered the Device.
device_exposure	quantity	int4	10	√		null	The number of individual Devices used for the exposure.
device_exposure	unique_device_id	varchar	50	√		null	A UDI or equivalent identifying the instance of the Device used in the Person.
device_exposure	visit_detail_id	int4	10	√		null	A foreign key to the visit in the visit-detail table during which the Drug Exposure was initiated.
device_exposure	visit_occurrence_id	int4	10	√		null	A foreign key to the visit in the VISIT table during which the device was used.
domain	domain_concept_id	int4	10				A foreign key that refers to an identifier in the [CONCEPT](https://github.com/OHDSI/CommonDataModel/wiki/CONCEPT) table for the unique Domain Concept the Domain record belongs to.
domain	domain_id	varchar	20				A unique key for each domain.
domain	domain_name	varchar	255				The name describing the Domain, e.g. "Condition", "Procedure", "Measurement" etc.
dose_era	dose_era_end_date	date	13				The end date for the drug era constructed from the individual instance of drug exposures. It is the end date of the final continuously recorded instance of utilization of a drug.
dose_era	dose_era_id	int4	10				A unique identifier for each Dose Era.
dose_era	dose_era_start_date	date	13				The start date for the drug era constructed from the individual instances of drug exposures. It is the start date of the very first chronologically recorded instance of utilization of a drug.
dose_era	dose_value	numeric	131089				The numeric value of the dose.
dose_era	drug_concept_id	int4	10				A foreign key that refers to a Standard Concept identifier in the Standardized Vocabularies for the active Ingredient Concept.
dose_era	person_id	int4	10				A foreign key identifier to the Person who is subjected to the drug during the drug era. The demographic details of that Person are stored in the PERSON table.
dose_era	unit_concept_id	int4	10				A foreign key that refers to a Standard Concept identifier in the Standardized Vocabularies for the unit concept.
drug_era	drug_concept_id	int4	10				A foreign key that refers to a Standard Concept identifier in the Standardized Vocabularies for the Ingredient Concept.
drug_era	drug_era_end_date	date	13				The end date for the drug era constructed from the individual instance of drug exposures. It is the end date of the final continuously recorded instance of utilization of a drug.
drug_era	drug_era_id	int4	10				A unique identifier for each Drug Era.
drug_era	drug_era_start_date	date	13				The start date for the Drug Era constructed from the individual instances of Drug Exposures. It is the start date of the very first chronologically recorded instance of conutilization of a Drug.
drug_era	drug_exposure_count	int4	10	√		null	The number of individual Drug Exposure occurrences used to construct the Drug Era.
drug_era	gap_days	int4	10	√		null	The number of days that are not covered by DRUG_EXPOSURE records that were used to make up the era record.
drug_era	person_id	int4	10				A foreign key identifier to the Person who is subjected to the Drug during the fDrug Era. The demographic details of that Person are stored in the PERSON table.
drug_exposure	days_supply	int4	10	√		null	The number of days of supply of the medication as recorded in the original prescription or dispensing record.
drug_exposure	dose_unit_source_value	varchar	50	√		null	The information about the dose unit as detailed in the source.
drug_exposure	drug_concept_id	int4	10				A foreign key that refers to a Standard Concept identifier in the Standardized Vocabularies for the Drug concept.
drug_exposure	drug_exposure_end_date	date	13				The end date for the current instance of Drug utilization. It is not available from all sources.
drug_exposure	drug_exposure_end_datetime	timestamp	29,6	√		null	The end date and time for the current instance of Drug utilization. It is not available from all sources.
drug_exposure	drug_exposure_id	int4	10				A system-generated unique identifier for each Drug utilization event.
drug_exposure	drug_exposure_start_date	date	13				The start date for the current instance of Drug utilization. Valid entries include a start date of a prescription, the date a prescription was filled, or the date on which a Drug administration procedure was recorded.
drug_exposure	drug_exposure_start_datetime	timestamp	29,6				The start date and time for the current instance of Drug utilization. Valid entries include a start date of a prescription, the date a prescription was filled, or the date on which a Drug administration procedure was recorded.
drug_exposure	drug_source_concept_id	int4	10	√		null	A foreign key to a Drug Concept that refers to the code used in the source.
drug_exposure	drug_source_value	varchar	50	√		null	The source code for the Drug as it appears in the source data. This code is mapped to a Standard Drug concept in the Standardized Vocabularies and the original code is, stored here for reference.
drug_exposure	drug_type_concept_id	int4	10				A foreign key to the predefined Concept identifier in the Standardized Vocabularies reflecting the type of Drug Exposure recorded. It indicates how the Drug Exposure was represented in the source data.
drug_exposure	lot_number	varchar	50	√		null	An identifier assigned to a particular quantity or lot of Drug product from the manufacturer.
drug_exposure	person_id	int4	10				A foreign key identifier to the person who is subjected to the Drug. The demographic details of that person are stored in the person table.
drug_exposure	provider_id	int4	10	√		null	A foreign key to the provider in the provider table who initiated (prescribed or administered) the Drug Exposure.
drug_exposure	quantity	numeric	131089	√		null	The quantity of drug as recorded in the original prescription or dispensing record.
drug_exposure	refills	int4	10	√		null	The number of refills after the initial prescription. The initial prescription is not counted, values start with 0.
drug_exposure	route_concept_id	int4	10	√		null	A foreign key to a predefined concept in the Standardized Vocabularies reflecting the route of administration.
drug_exposure	route_source_value	varchar	50	√		null	The information about the route of administration as detailed in the source.
drug_exposure	sig	text	2147483647	√		null	The directions ("signetur") on the Drug prescription as recorded in the original prescription (and printed on the container) or dispensing record.
drug_exposure	stop_reason	varchar	20	√		null	The reason the Drug was stopped. Reasons include regimen completed, changed, removed, etc.
drug_exposure	verbatim_end_date	date	13	√		null	The known end date of a drug_exposure as provided by the source
drug_exposure	visit_detail_id	int4	10	√		null	A foreign key to the visit in the VISIT_DETAIL table during which the Drug Exposure was initiated.
drug_exposure	visit_occurrence_id	int4	10	√		null	A foreign key to the visit in the visit table during which the Drug Exposure was initiated.
drug_strength	amount_unit_concept_id	int4	10	√		null	A foreign key to the Concept in the CONCEPT table representing the identifier for the Unit for the absolute amount of active ingredient.
drug_strength	amount_value	numeric	131089	√		null	The numeric value associated with the amount of active ingredient contained within the product.
drug_strength	box_size	int4	10	√		null	The number of units of Clinical of Branded Drug, or Quantified Clinical or Branded Drug contained in a box as dispensed to the patient
drug_strength	denominator_unit_concept_id	int4	10	√		null	A foreign key to the Concept in the CONCEPT table representing the identifier for the denominator Unit for the concentration of active ingredient.
drug_strength	denominator_value	numeric	131089	√		null	The amount of total liquid (or other divisible product, such as ointment, gel, spray, etc.).
drug_strength	drug_concept_id	int4	10				A foreign key to the Concept in the CONCEPT table representing the identifier for Branded Drug or Clinical Drug Concept.
drug_strength	ingredient_concept_id	int4	10				A foreign key to the Concept in the CONCEPT table, representing the identifier for drug Ingredient Concept contained within the drug product.
drug_strength	invalid_reason	varchar	1	√		null	Reason the concept was invalidated. Possible values are 'D'(deleted), 'U'(replaced with an update) or NULL when valid_end_date has the default value.
drug_strength	numerator_unit_concept_id	int4	10	√		null	A foreign key to the Concept in the CONCEPT table representing the identifier for the numerator Unit for the concentration of active ingredient.
drug_strength	numerator_value	numeric	131089	√		null	The numeric value associated with the concentration of the active ingredient contained in the product
drug_strength	valid_end_date	date	13				The date when the concept became invalid because it was deleted or superseded (updated) by a new Concept. The default value is 31-Dec-2099.
drug_strength	valid_start_date	date	13				The date when the Concept was first recorded. The default value is 1-Jan-1970.
fact_relationship	domain_concept_id_1	int4	10				The concept representing the domain of fact one, from which the corresponding table can be inferred.
fact_relationship	domain_concept_id_2	int4	10				The concept representing the domain of fact two, from which the corresponding table can be inferred.
fact_relationship	fact_id_1	int4	10				The unique identifier in the table corresponding to the domain of fact one.
fact_relationship	fact_id_2	int4	10				The unique identifier in the table corresponding to the domain of fact two.
fact_relationship	relationship_concept_id	int4	10				A foreign key to a Standard Concept ID of relationship in the Standardized Vocabularies.
location	address_1	varchar	50	√		null	The address field 1, typically used for the street address, as it appears in the source data.
location	address_2	varchar	50	√		null	The address field 2, typically used for additional detail such as buildings, suites, floors, as it appears in the source data.
location	city	varchar	50	√		null	The city field as it appears in the source data.
location	county	varchar	20	√		null	The county.
location	location_id	int4	10				A unique identifier for each geographic location.
location	location_source_value	varchar	50	√		null	The verbatim information that is used to uniquely identify the location as it appears in the source data.
location	state	varchar	2	√		null	The state field as it appears in the source data.
location	zip	varchar	9	√		null	The zip or postal code.
measurement	measurement_concept_id	int4	10				A foreign key to the standard measurement concept identifier in the Standardized Vocabularies.
measurement	measurement_date	date	13				The date of the Measurement.
measurement	measurement_datetime	timestamp	29,6	√		null	The date and time of the Measurement. Some database systems don't have a datatype of time. To accomodate all temporal analyses, datatype datetime can be used (combining measurement_date and measurement_time [forum discussion](http://forums.ohdsi.org/t/date-time-and-datetime-problem-and-the-world-of-hours-and-1day/314))
measurement	measurement_id	int4	10				A unique identifier for each Measurement.
measurement	measurement_source_concept_id	int4	10	√		null	A foreign key to a Concept in the Standard Vocabularies that refers to the code used in the source.
measurement	measurement_source_value	varchar	50	√		null	The Measurement name as it appears in the source data. This code is mapped to a Standard Concept in the Standardized Vocabularies and the original code is stored here for reference.
measurement	measurement_type_concept_id	int4	10				A foreign key to the predefined Concept in the Standardized Vocabularies reflecting the provenance from where the Measurement record was recorded.
measurement	operator_concept_id	int4	10	√		null	A foreign key identifier to the predefined Concept in the Standardized Vocabularies reflecting the mathematical operator that is applied to the value_as_number. Operators are <, <=, =, >=, >.
measurement	person_id	int4	10				A foreign key identifier to the Person about whom the measurement was recorded. The demographic details of that Person are stored in the PERSON table.
measurement	provider_id	int4	10	√		null	A foreign key to the provider in the PROVIDER table who was responsible for initiating or obtaining the measurement.
measurement	range_high	numeric	131089	√		null	The upper limit of the normal range of the Measurement. The upper range is assumed to be of the same unit of measure as the Measurement value.
measurement	range_low	numeric	131089	√		null	The lower limit of the normal range of the Measurement result. The lower range is assumed to be of the same unit of measure as the Measurement value.
measurement	unit_concept_id	int4	10	√		null	A foreign key to a Standard Concept ID of Measurement Units in the Standardized Vocabularies.
measurement	unit_source_value	varchar	50	√		null	The source code for the unit as it appears in the source data. This code is mapped to a standard unit concept in the Standardized Vocabularies and the original code is stored here for reference.
measurement	value_as_concept_id	int4	10	√		null	A foreign key to a Measurement result represented as a Concept from the Standardized Vocabularies (e.g., positive/negative, present/absent, low/high, etc.).
measurement	value_as_number	numeric	131089	√		null	A Measurement result where the result is expressed as a numeric value.
measurement	value_source_value	varchar	50	√		null	The source value associated with the content of the value_as_number or value_as_concept_id as stored in the source data.
measurement	visit_detail_id	int4	10	√		null	A foreign key to the Visit in the VISIT_DETAIL table during which the Measurement was recorded.
measurement	visit_occurrence_id	int4	10	√		null	A foreign key to the Visit in the VISIT_OCCURRENCE table during which the Measurement was recorded.
note	encoding_concept_id	int4	10				A foreign key to the predefined Concept in the Standardized Vocabularies reflecting the note character encoding type
note	language_concept_id	int4	10				A foreign key to the predefined Concept in the Standardized Vocabularies reflecting the language of the note
note	note_class_concept_id	int4	10				A foreign key to the predefined Concept in the Standardized Vocabularies reflecting the HL7 LOINC Document Type Vocabulary classification of the note.
note	note_date	date	13				The date the note was recorded.
note	note_datetime	timestamp	29,6	√		null	The date and time the note was recorded.
note	note_id	int4	10				A unique identifier for each note.
note	note_source_value	varchar	50	√		null	The source value associated with the origin of the note
note	note_text	text	2147483647				The content of the Note.
note	note_title	varchar	250	√		null	The title of the Note as it appears in the source.
note	note_type_concept_id	int4	10				A foreign key to the predefined Concept in the Standardized Vocabularies reflecting the type, origin or provenance of the Note.
note	person_id	int4	10				A foreign key identifier to the Person about whom the Note was recorded. The demographic details of that Person are stored in the PERSON table.
note	provider_id	int4	10	√		null	A foreign key to the Provider in the PROVIDER table who took the Note.
note	visit_detail_id	int4	10	√		null
note	visit_occurrence_id	int4	10	√		null	Foreign key to the Visit in the VISIT_OCCURRENCE table when the Note was taken.
note_nlp	lexical_variant	varchar	250				Raw text extracted from the NLP tool.
note_nlp	nlp_date	date	13				The date of the note processing.Useful for data provenance.
note_nlp	nlp_datetime	timestamp	29,6	√		null	The date and time of the note processing. Useful for data provenance.
note_nlp	nlp_system	varchar	250	√		null	Name and version of the NLP system that extracted the term.Useful for data provenance.
note_nlp	note_id	int4	10				A foreign key to the Note table note the term was extracted from.
note_nlp	note_nlp_concept_id	int4	10	√		null	A foreign key to the predefined Concept in the Standardized Vocabularies reflecting the normalized concept for the extracted term. Domain of the term is represented as part of the Concept table.
note_nlp	note_nlp_id	int8	19				A unique identifier for each term extracted from a note.
note_nlp	note_nlp_source_concept_id	int4	10	√		null	A foreign key to a Concept that refers to the code in the source vocabulary used by the NLP system
note_nlp	offset	varchar	250	√		null	Character offset of the extracted term in the input note.
note_nlp	section_concept_id	int4	10	√		null	A foreign key to the predefined Concept in the Standardized Vocabularies representing the section of the extracted term.
note_nlp	snippet	varchar	250	√		null	A small window of text surrounding the term.
note_nlp	term_exists	varchar	1	√		null	A summary modifier that signifies presence or absence of the term for a given patient. Useful for quick querying. *
note_nlp	term_modifiers	varchar	2000	√		null
note_nlp	term_temporal	varchar	50	√		null
observation	observation_concept_id	int4	10				A foreign key to the standard observation concept identifier in the Standardized Vocabularies.
observation	observation_date	date	13				The date of the observation.
observation	observation_datetime	timestamp	29,6	√		null	The date and time of the observation.
observation	observation_id	int4	10				A unique identifier for each observation.
observation	observation_source_concept_id	int4	10	√		null	A foreign key to a Concept that refers to the code used in the source.
observation	observation_source_value	varchar	50	√		null	The observation code as it appears in the source data. This code is mapped to a Standard Concept in the Standardized Vocabularies and the original code is, stored here for reference.
observation	observation_type_concept_id	int4	10				A foreign key to the predefined concept identifier in the Standardized Vocabularies reflecting the type of the observation.
observation	person_id	int4	10				A foreign key identifier to the Person about whom the observation was recorded. The demographic details of that Person are stored in the PERSON table.
observation	provider_id	int4	10	√		null	A foreign key to the provider in the PROVIDER table who was responsible for making the observation.
observation	qualifier_concept_id	int4	10	√		null	A foreign key to a Standard Concept ID for a qualifier (e.g., severity of drug-drug interaction alert)
observation	qualifier_source_value	varchar	50	√		null	The source value associated with a qualifier to characterize the observation
observation	unit_concept_id	int4	10	√		null	A foreign key to a Standard Concept ID of measurement units in the Standardized Vocabularies.
observation	unit_source_value	varchar	50	√		null	The source code for the unit as it appears in the source data. This code is mapped to a standard unit concept in the Standardized Vocabularies and the original code is, stored here for reference.
observation	value_as_concept_id	int4	10	√		null	A foreign key to an observation result stored as a Concept ID. This is applicable to observations where the result can be expressed as a Standard Concept from the Standardized Vocabularies (e.g., positive/negative, present/absent, low/high, etc.).
observation	value_as_number	numeric	131089	√		null	The observation result stored as a number. This is applicable to observations where the result is expressed as a numeric value.
observation	value_as_string	varchar	60	√		null	The observation result stored as a string. This is applicable to observations where the result is expressed as verbatim text.
observation	visit_detail_id	int4	10	√		null	A foreign key to the visit in the VISIT_DETAIL table during which the observation was recorded.
observation	visit_occurrence_id	int4	10	√		null	A foreign key to the visit in the VISIT_OCCURRENCE table during which the observation was recorded.
observation_period	observation_period_end_date	date	13				The end date of the observation period for which data are available from the data source.
observation_period	observation_period_end_datetime	timestamp	29,6
observation_period	observation_period_id	int4	10				A unique identifier for each observation period.
observation_period	observation_period_start_date	date	13				The start date of the observation period for which data are available from the data source.
observation_period	observation_period_start_datetime	timestamp	29,6
observation_period	period_type_concept_id	int4	10				A foreign key identifier to the predefined concept in the Standardized Vocabularies reflecting the source of the observation period information
observation_period	person_id	int4	10				A foreign key identifier to the person for whom the observation period is defined. The demographic details of that person are stored in the person table.
payer_plan_period	family_source_value	varchar	50	√		null	The source code for the Person's family as it appears in the source data.
payer_plan_period	payer_plan_period_end_date	date	13				The end date of the payer plan period.
payer_plan_period	payer_plan_period_id	int4	10				A identifier for each unique combination of payer, plan, family code and time span.
payer_plan_period	payer_plan_period_start_date	date	13				The start date of the payer plan period.
payer_plan_period	payer_source_value	varchar	50	√		null	The source code for the payer as it appears in the source data.
payer_plan_period	person_id	int4	10				A foreign key identifier to the Person covered by the payer. The demographic details of that Person are stored in the PERSON table.
payer_plan_period	plan_source_value	varchar	50	√		null	The source code for the Person's health benefit plan as it appears in the source data.
person	birth_datetime	timestamp	29,6	√		null	The date and time of birth of the person.
person	care_site_id	int4	10	√		null	A foreign key to the site of primary care in the care_site table, where the details of the care site are stored.
person	day_of_birth	int4	10	√		null	The day of the month of birth of the person. For data sources that provide the precise date of birth, the day is extracted and stored in this field.
person	ethnicity_concept_id	int4	10				A foreign key that refers to the standard concept identifier in the Standardized Vocabularies for the ethnicity of the person.
person	ethnicity_source_concept_id	int4	10	√		null	A foreign key to the ethnicity concept that refers to the code used in the source.
person	ethnicity_source_value	varchar	50	√		null	The source code for the ethnicity of the person as it appears in the source data. The person ethnicity is mapped to a standard ethnicity concept in the Standardized Vocabularies and the original code is, stored here for reference.
person	gender_concept_id	int4	10				A foreign key that refers to an identifier in the CONCEPT table for the unique gender of the person.
person	gender_source_concept_id	int4	10	√		null	A foreign key to the gender concept that refers to the code used in the source.
person	gender_source_value	varchar	50	√		null	The source code for the gender of the person as it appears in the source data. The person?s gender is mapped to a standard gender concept in the Standardized Vocabularies; the original value is stored here for reference.
person	location_id	int4	10	√		null	A foreign key to the place of residency for the person in the location table, where the detailed address information is stored.
person	month_of_birth	int4	10	√		null	The month of birth of the person. For data sources that provide the precise date of birth, the month is extracted and stored in this field.
person	person_id	int4	10				A unique identifier for each person.
person	person_source_value	varchar	50	√		null	An (encrypted) key derived from the person identifier in the source data. This is necessary when a use case requires a link back to the person data at the source dataset.
person	provider_id	int4	10	√		null	A foreign key to the primary care provider the person is seeing in the provider table.
person	race_concept_id	int4	10				A foreign key that refers to an identifier in the CONCEPT table for the unique race of the person.
person	race_source_concept_id	int4	10	√		null	A foreign key to the race concept that refers to the code used in the source.
person	race_source_value	varchar	50	√		null	The source code for the race of the person as it appears in the source data. The person race is mapped to a standard race concept in the Standardized Vocabularies and the original value is stored here for reference.
person	year_of_birth	int4	10				The year of birth of the person. For data sources with date of birth, the year is extracted. For data sources where the year of birth is not available, the approximate year of birth is derived based on any age group categorization available.
procedure_occurrence	modifier_concept_id	int4	10	√		null	A foreign key to a Standard Concept identifier for a modifier to the Procedure (e.g. bilateral)
procedure_occurrence	person_id	int4	10				A foreign key identifier to the Person who is subjected to the Procedure. The demographic details of that Person are stored in the PERSON table.
procedure_occurrence	procedure_concept_id	int4	10				A foreign key that refers to a standard procedure Concept identifier in the Standardized Vocabularies.
procedure_occurrence	procedure_date	date	13				The date on which the Procedure was performed.
procedure_occurrence	procedure_datetime	timestamp	29,6				The date and time on which the Procedure was performed.
procedure_occurrence	procedure_occurrence_id	int4	10				A system-generated unique identifier for each Procedure Occurrence.
procedure_occurrence	procedure_source_concept_id	int4	10	√		null	A foreign key to a Procedure Concept that refers to the code used in the source.
procedure_occurrence	procedure_source_value	varchar	50	√		null	The source code for the Procedure as it appears in the source data. This code is mapped to a standard procedure Concept in the Standardized Vocabularies and the original code is, stored here for reference. Procedure source codes are typically ICD-9-Proc, CPT-4, HCPCS or OPCS-4 codes.
procedure_occurrence	procedure_type_concept_id	int4	10				A foreign key to the predefined Concept identifier in the Standardized Vocabularies reflecting the type of source data from which the procedure record is derived.
procedure_occurrence	provider_id	int4	10	√		null	A foreign key to the provider in the provider table who was responsible for carrying out the procedure.
procedure_occurrence	qualifier_source_value	varchar	50	√		null	The source code for the qualifier as it appears in the source data.
procedure_occurrence	quantity	int4	10	√		null	The quantity of procedures ordered or administered.
procedure_occurrence	visit_detail_id	int4	10	√		null	A foreign key to the visit in the visit table during which the Procedure was carried out.
procedure_occurrence	visit_occurrence_id	int4	10	√		null	A foreign key to the visit in the visit table during which the Procedure was carried out.
provider	care_site_id	int4	10	√		null	A foreign key to the main Care Site where the provider is practicing.
provider	dea	varchar	20	√		null	The Drug Enforcement Administration (DEA) number of the provider.
provider	gender_concept_id	int4	10	√		null	The gender of the Provider.
provider	gender_source_concept_id	int4	10	√		null	A foreign key to a Concept that refers to the code used in the source.
provider	gender_source_value	varchar	50	√		null	The gender code for the Provider as it appears in the source data, stored here for reference.
provider	npi	varchar	20	√		null	The National Provider Identifier (NPI) of the provider.
provider	provider_id	int4	10				A unique identifier for each Provider.
provider	provider_name	varchar	255	√		null	A description of the Provider.
provider	provider_source_value	varchar	50	√		null	The identifier used for the Provider in the source data, stored here for reference.
provider	specialty_concept_id	int4	10	√		null	A foreign key to a Standard Specialty Concept ID in the Standardized Vocabularies.
provider	specialty_source_concept_id	int4	10	√		null	A foreign key to a Concept that refers to the code used in the source.
provider	specialty_source_value	varchar	50	√		null	The source code for the Provider specialty as it appears in the source data, stored here for reference.
provider	year_of_birth	int4	10	√		null	The year of birth of the Provider.
relationship	defines_ancestry	varchar	1				Defines whether a hierarchical relationship contributes to the concept_ancestor table. These are subsets of the hierarchical relationships. Valid values are 1 or 0.
relationship	is_hierarchical	varchar	1				Defines whether a relationship defines concepts into classes or hierarchies. Values are 1 for hierarchical relationship or 0 if not.
relationship	relationship_concept_id	int4	10				A foreign key that refers to an identifier in the CONCEPT table for the unique relationship concept.
relationship	relationship_id	varchar	20				The type of relationship captured by the relationship record.
relationship	relationship_name	varchar	255				The text that describes the relationship type.
relationship	reverse_relationship_id	varchar	20				The identifier for the relationship used to define the reverse relationship between two concepts.
source_to_concept_map	invalid_reason	varchar	1	√		null	Reason the mapping instance was invalidated. Possible values are D (deleted), U (replaced with an update) or NULL when valid_end_date has the default value.
source_to_concept_map	source_code	varchar	50				The source code being translated into a Standard Concept.
source_to_concept_map	source_code_description	varchar	255	√		null	An optional description for the source code. This is included as a convenience to compare the description of the source code to the name of the concept.
source_to_concept_map	source_concept_id	int4	10				A foreign key to the Source Concept that is being translated into a Standard Concept.
source_to_concept_map	source_vocabulary_id	varchar	20				A foreign key to the VOCABULARY table defining the vocabulary of the source code that is being translated to a Standard Concept.
source_to_concept_map	target_concept_id	int4	10				A foreign key to the target Concept to which the source code is being mapped.
source_to_concept_map	target_vocabulary_id	varchar	20				A foreign key to the VOCABULARY table defining the vocabulary of the target Concept.
source_to_concept_map	valid_end_date	date	13				The date when the mapping instance became invalid because it was deleted or superseded (updated) by a new relationship. Default value is 31-Dec-2099.
source_to_concept_map	valid_start_date	date	13				The date when the mapping instance was first recorded.
specimen	anatomic_site_concept_id	int4	10	√		null	A foreign key to a Standard Concept identifier for the anatomic location of specimen collection.
specimen	anatomic_site_source_value	varchar	50	√		null	The information about the anatomic site as detailed in the source.
specimen	disease_status_concept_id	int4	10	√		null	A foreign key to a Standard Concept identifier for the Disease Status of specimen collection.
specimen	disease_status_source_value	varchar	50	√		null	The information about the disease status as detailed in the source.
specimen	person_id	int4	10				A foreign key identifier to the Person for whom the Specimen is recorded.
specimen	quantity	numeric	131089	√		null	The amount of specimen collection from the person during the sampling procedure.
specimen	specimen_concept_id	int4	10				A foreign key referring to a Standard Concept identifier in the Standardized Vocabularies for the Specimen.
specimen	specimen_date	date	13				The date the specimen was obtained from the Person.
specimen	specimen_datetime	timestamp	29,6	√		null	The date and time on the date when the Specimen was obtained from the person.
specimen	specimen_id	int4	10				A unique identifier for each specimen.
specimen	specimen_source_id	varchar	50	√		null	The Specimen identifier as it appears in the source data.
specimen	specimen_source_value	varchar	50	√		null	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.
specimen	specimen_type_concept_id	int4	10				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	unit_concept_id	int4	10	√		null	A foreign key to a Standard Concept identifier for the Unit associated with the numeric quantity of the Specimen collection.
specimen	unit_source_value	varchar	50	√		null	The information about the Unit as detailed in the source.
visit_detail	admitting_source_concept_id	int4	10	√		null	A foreign key to the predefined concept in the Place of Service Vocabulary reflecting the admitting source for a visit.
visit_detail	admitting_source_value	varchar	50	√		null	The source code for the admitting source as it appears in the source data.
visit_detail	care_site_id	int4	10	√		null	A foreign key to the care site in the care site table that was visited.
visit_detail	discharge_to_concept_id	int4	10	√		null	A foreign key to the predefined concept in the Place of Service Vocabulary reflecting the discharge disposition for a visit.
visit_detail	discharge_to_source_value	varchar	50	√		null	The source code for the discharge disposition as it appears in the source data.
visit_detail	person_id	int4	10				A foreign key identifier to the Person for whom the visit is recorded. The demographic details of that Person are stored in the PERSON table.
visit_detail	preceding_visit_detail_id	int4	10	√		null	A foreign key to the VISIT_DETAIL table of the visit immediately preceding this visit
visit_detail	provider_id	int4	10	√		null	A foreign key to the provider in the provider table who was associated with the visit.
visit_detail	visit_detail_concept_id	int4	10				A foreign key that refers to a visit Concept identifier in the Standardized Vocabularies.
visit_detail	visit_detail_id	int4	10				A unique identifier for each Person's visit or encounter at a healthcare provider.
visit_detail	visit_detail_parent_id	int4	10	√		null	A foreign key to the VISIT_DETAIL table record to represent the immediate parent visit-detail record.
visit_detail	visit_end_date	date	13				The end date of the visit. If this is a one-day visit the end date should match the start date.
visit_detail	visit_end_datetime	timestamp	29,6	√		null	The date and time of the visit end.
visit_detail	visit_occurrence_id	int4	10	√		null	A foreign key that refers to the record in the VISIT_OCCURRENCE table. This is a required field, because for every visit_detail is a child of visit_occurrence and cannot exist without a corresponding parent record in visit_occurrence.
visit_detail	visit_source_concept_id	int4	10	√		null	A foreign key to a Concept that refers to the code used in the source.
visit_detail	visit_source_value	varchar	50	√		null	The source code for the visit as it appears in the source data.
visit_detail	visit_start_date	date	13				The start date of the visit.
visit_detail	visit_start_datetime	timestamp	29,6	√		null	The date and time of the visit started.
visit_detail	visit_type_concept_id	int4	10				A foreign key to the predefined Concept identifier in the Standardized Vocabularies reflecting the type of source data from which the visit record is derived.
visit_occurrence	admitting_source_concept_id	int4	10	√		null	A foreign key to the predefined concept in the Place of Service Vocabulary reflecting the admitting source for a visit.
visit_occurrence	admitting_source_value	varchar	50	√		null	The source code for the admitting source as it appears in the source data.
visit_occurrence	care_site_id	int4	10	√		null	A foreign key to the care site in the care site table that was visited.
visit_occurrence	discharge_to_concept_id	int4	10	√		null	A foreign key to the predefined concept in the Place of Service Vocabulary reflecting the discharge disposition for a visit.
visit_occurrence	discharge_to_source_value	varchar	50	√		null	The source code for the discharge disposition as it appears in the source data.
visit_occurrence	person_id	int4	10				A foreign key identifier to the Person for whom the visit is recorded. The demographic details of that Person are stored in the PERSON table.
visit_occurrence	preceding_visit_occurrence_id	int4	10	√		null	A foreign key to the VISIT_OCCURRENCE table of the visit immediately preceding this visit
visit_occurrence	provider_id	int4	10	√		null	A foreign key to the provider in the provider table who was associated with the visit.
visit_occurrence	visit_concept_id	int4	10				A foreign key that refers to a visit Concept identifier in the Standardized Vocabularies.
visit_occurrence	visit_end_date	date	13				The end date of the visit. If this is a one-day visit the end date should match the start date.
visit_occurrence	visit_end_datetime	timestamp	29,6	√		null	The date and time of the visit end.
visit_occurrence	visit_occurrence_id	int4	10				A unique identifier for each Person's visit or encounter at a healthcare provider.
visit_occurrence	visit_source_concept_id	int4	10	√		null	A foreign key to a Concept that refers to the code used in the source.
visit_occurrence	visit_source_value	varchar	50	√		null	The source code for the visit as it appears in the source data.
visit_occurrence	visit_start_date	date	13				The start date of the visit.
visit_occurrence	visit_start_datetime	timestamp	29,6	√		null	The date and time of the visit started.
visit_occurrence	visit_type_concept_id	int4	10				A foreign key to the predefined Concept identifier in the Standardized Vocabularies reflecting the type of source data from which the visit record is derived.
vocabulary	vocabulary_concept_id	int4	10				A foreign key that refers to a standard concept identifier in the CONCEPT table for the Vocabulary the VOCABULARY record belongs to.
vocabulary	vocabulary_id	varchar	20				A unique identifier for each Vocabulary, such as ICD9CM, SNOMED, Visit.
vocabulary	vocabulary_name	varchar	255				The name describing the vocabulary, for example "International Classification of Diseases, Ninth Revision, Clinical Modification, Volume 1 and 2 (NCHS)" etc.
vocabulary	vocabulary_reference	varchar	255	√		null	External reference to documentation or available download of the about the vocabulary.
vocabulary	vocabulary_version	varchar	255	√		null	Version of the Vocabulary as indicated in the source.