DRUG_EXPOSURE

Table Description

This table captures records about the exposure to a Drug ingested or otherwise introduced into the body. A Drug is a biochemical substance formulated in such a way that when administered to a Person it will exert a certain biochemical effect on the metabolism. Drugs include prescription and over-the-counter medicines, vaccines, and large-molecule biologic therapies. Radiological devices ingested or applied locally do not count as Drugs.

User Guide

The purpose of records in this table is to indicate an exposure to a certain drug as best as possible. In this context a drug is defined as an active ingredient. Drug Exposures are defined by Concepts from the Drug domain, which form a complex hierarchy. As a result, one DRUG_SOURCE_CONCEPT_ID may map to multiple standard concept ids if it is a combination product. Records in this table represent prescriptions written, prescriptions dispensed, and drugs administered by a provider to name a few. The DRUG_TYPE_CONCEPT_ID can be used to find and filter on these types. This table includes additional information about the drug products, the quantity given, and route of administration.

ETL Conventions

Information about quantity and dose is provided in a variety of different ways and it is important for the ETL to provide as much information as possible from the data. Depending on the provenance of the data fields may be captured differently i.e. quantity for drugs administered may have a separate meaning from quantity for prescriptions dispensed. If a patient has multiple records on the same day for the same drug or procedures the ETL should not de-dupe them unless there is probable reason to believe the item is a true data duplicate. Take note on how to handle refills for prescriptions written.

CDM Field	User Guide	ETL Conventions	Datatype	Required	Primary Key	Foreign Key	FK Table	FK Domain
drug_exposure_id	The unique key given to records of drug dispensings or administrations for a person. Refer to the ETL for how duplicate drugs during the same visit were handled.	Each instance of a drug dispensing or administration present in the source data should be assigned this unique key. In some cases, a person can have multiple records of the same drug within the same visit. It is valid to keep these duplicates and assign them individual, unique, DRUG_EXPOSURE_IDs, though it is up to the ETL how they should be handled.	integer	Yes	Yes	No
person_id	The PERSON_ID of the PERSON for whom the drug dispensing or administration is recorded. This may be a system generated code.		integer	Yes	No	Yes	PERSON
drug_concept_id	The DRUG_CONCEPT_ID field is recommended for primary use in analyses, and must be used for network studies. This is the standard concept mapped from the source concept id which represents a drug product or molecule otherwise introduced to the body. The drug concepts can have a varying degree of information about drug strength and dose. This information is relevant in the context of quantity and administration information in the subsequent fields plus strength information from the DRUG_STRENGTH table, provided as part of the standard vocabulary download.	The CONCEPT_ID that the DRUG_SOURCE_VALUE maps to. The concept id should be derived either from mapping from the source concept id or by picking the drug concept representing the most amount of detail you have. Records whose source values map to standard concepts with a domain of Drug should go in this table. When the Drug Source Value of the code cannot be translated into Standard Drug Concept IDs, a Drug exposure entry is stored with only the corresponding SOURCE_CONCEPT_ID and DRUG_SOURCE_VALUE and a DRUG_CONCEPT_ID of 0. The Drug Concept with the most detailed content of information is preferred during the mapping process. These are indicated in the CONCEPT_CLASS_ID field of the Concept and are recorded in the following order of precedence: ‘Branded Pack’, ‘Clinical Pack’, ‘Branded Drug’, ‘Clinical Drug’, ‘Branded Drug Component’, ‘Clinical Drug Component’, ‘Branded Drug Form’, ‘Clinical Drug Form’, and only if no other information is available ‘Ingredient’. Note: If only the drug class is known, the DRUG_CONCEPT_ID field should contain 0. Accepted Concepts.	integer	Yes	No	Yes	CONCEPT	Drug
drug_exposure_start_date	Use this date to determine the start date of the drug record.	Valid entries include a start date of a prescription, the date a prescription was filled, or the date on which a Drug administration was recorded. It is a valid ETL choice to use the date the drug was ordered as the DRUG_EXPOSURE_START_DATE.	date	Yes	No	No
drug_exposure_start_datetime		This is not required, though it is in v6. If a source does not specify datetime the convention is to set the time to midnight (00:00:0000)	datetime	No	No	No
drug_exposure_end_date	The DRUG_EXPOSURE_END_DATE denotes the day the drug exposure ended for the patient.	If this information is not explicitly available in the data, infer the end date using the following methods: 1. Start first with duration or days supply using the calculation drug start date + days supply -1 day. 2. Use quantity divided by daily dose that you may obtain from the sig or a source field (or assumed daily dose of 1) for solid, indivisibile, drug products. If quantity represents ingredient amount, quantity divided by daily dose * concentration (from drug_strength) drug concept id tells you the dose form. 3. If it is an administration record, set drug end date equal to drug start date. If the record is a written prescription then set end date to start date + 29. If the record is a mail-order prescription set end date to start date + 89. The end date must be equal to or greater than the start date. Ibuprofen 20mg/mL oral solution concept tells us this is oral solution. Calculate duration as quantity (200 example) * daily dose (5mL) /concentration (20mg/mL) 200*5/20 = 50 days. Examples by dose form	date	Yes	No	No
drug_exposure_end_datetime		This is not required, though it is in v6. If a source does not specify datetime the convention is to set the time to midnight (00:00:0000)	datetime	No	No	No
verbatim_end_date	This is the end date of the drug exposure as it appears in the source data, if it is given	Put the end date or discontinuation date as it appears from the source data or leave blank if unavailable.	date	No	No	No
drug_type_concept_id	You can use the TYPE_CONCEPT_ID to delineate between prescriptions written vs. prescriptions dispensed vs. medication history vs. patient-reported exposure, etc.	Choose the drug_type_concept_id that best represents the provenance of the record, for example whether it came from a record of a prescription written or physician administered drug. Accepted Concepts. A more detailed explanation of each Type Concept can be found on the vocabulary wiki.	integer	Yes	No	Yes	CONCEPT	Type Concept
stop_reason	The reason a person stopped a medication as it is represented in the source. Reasons include regimen completed, changed, removed, etc. This field will be retired in v6.0.	This information is often not populated in source data and it is a valid etl choice to leave it blank if the information does not exist.	varchar(20)	No	No	No
refills	This is only filled in when the record is coming from a prescription written this field is meant to represent intended refills at time of the prescription.		integer	No	No	No
quantity		To find the dose form of a drug the RELATIONSHIP table can be used where the relationship_id is ‘Has dose form’. If liquid, quantity stands for the total amount dispensed or ordered of ingredient in the units given by the drug_strength table. If the unit from the source data does not align with the unit in the DRUG_STRENGTH table the quantity should be converted to the correct unit given in DRUG_STRENGTH. For clinical drugs with fixed dose forms (tablets etc.) the quantity is the number of units/tablets/capsules prescribed or dispensed (can be partial, but then only 1/2 or 1/3, not 0.01). Clinical drugs with divisible dose forms (injections) the quantity is the amount of ingredient the patient got. For example, if the injection is 2mg/mL but the patient got 80mL then quantity is reported as 160. Quantified clinical drugs with divisible dose forms (prefilled syringes), the quantity is the amount of ingredient similar to clinical drugs. Please see how to calculate drug dose for more information.	float	No	No	No
days_supply		Days supply of the drug. This should be the verbatim days_supply as given on the prescription. If the drug is physician administered use duration end date if given or set to 1 as default if duration is not available.	integer	No	No	No
sig	This is the verbatim instruction for the drug as written by the provider.	Put the written out instructions for the drug as it is verbatim in the source, if available.	varchar(MAX)	No	No	No
route_concept_id		The standard CONCEPT_ID that the ROUTE_SOURCE_VALUE maps to in the route domain.	integer	No	No	Yes	CONCEPT	Route
lot_number			varchar(50)	No	No	No
provider_id	The Provider associated with drug record, e.g. the provider who wrote the prescription or the provider who administered the drug.	The ETL may need to make a choice as to which PROVIDER_ID to put here. Based on what is available this may or may not be different than the provider associated with the overall VISIT_OCCURRENCE record, for example the ordering vs administering physician on an EHR record.	integer	No	No	Yes	PROVIDER
visit_occurrence_id	The Visit during which the drug was prescribed, administered or dispensed.	To populate this field drug exposures must be explicitly initiated in the visit.	integer	No	No	Yes	VISIT_OCCURRENCE
visit_detail_id	The VISIT_DETAIL record during which the drug exposure occurred. For example, if the person was in the ICU at the time of the drug administration the VISIT_OCCURRENCE record would reflect the overall hospital stay and the VISIT_DETAIL record would reflect the ICU stay during the hospital visit.	Same rules apply as for the VISIT_OCCURRENCE_ID.	integer	No	No	Yes	VISIT_DETAIL
drug_source_value	This field houses the verbatim value from the source data representing the drug exposure that occurred. For example, this could be an NDC or Gemscript code.	This code is mapped to a Standard Drug Concept in the Standardized Vocabularies and the original code is stored here for reference.	varchar(50)	No	No	No
drug_source_concept_id	This is the concept representing the drug source value and may not necessarily be standard. This field is discouraged from use in analysis because it is not required to contain Standard Concepts that are used across the OHDSI community, and should only be used when Standard Concepts do not adequately represent the source detail for the Drug necessary for a given analytic use case. Consider using DRUG_CONCEPT_ID instead to enable standardized analytics that can be consistent across the network.	If the DRUG_SOURCE_VALUE is coded in the source data using an OMOP supported vocabulary put the concept id representing the source value here.	integer	No	No	Yes	CONCEPT
route_source_value	This field houses the verbatim value from the source data representing the drug route.	This information may be called something different in the source data but the field is meant to contain a value indicating when and how a drug was given to a patient. This source value is mapped to a standard concept which is stored in the ROUTE_CONCEPT_ID field.	varchar(50)	No	No	No
dose_unit_source_value	This field houses the verbatim value from the source data representing the dose unit of the drug given.	This information may be called something different in the source data but the field is meant to contain a value indicating the unit of dosage of drug given to the patient. This is an older column and will be deprecated in an upcoming version.	varchar(50)	No	No	No