===== Drug Quantity =====
=== Proposals are now being tracked as github issues ===
[[https://github.com/OHDSI/CommonDataModel/issues/73|link to github issue]]

  * Requesters: Christian Reich, Klaus Bonadt

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==== Proposal ====
We propose to abolish the effective_drug_dose field from the DRUG_EXPOSURE table entirely. The content can be handled by the quantity table.

== Background ==
We need to have a way to define drug_strength if we have no product information, but only ingredients or drug forms, or if like in chemotherapies or pediatric preparations the drug strength is not defined by the product. 

Currently, this information is stored as:

drug_concept_id - contains the ingredient
quantity or effective drug_dose - value
nowhere or dose_unit_concept_id - unit

This works well for ingredients and uni-ingredient drug forms. We should however define a single way of doing it.

Also, we have a problem with multi-ingredient drug forms, because we only have one field.

=== Use Cases ===

Calculation of daily or total dose of a DRUG_EXPOSURE record.

=== Proposal ===

All dosing information is handled through single ingredients stored in the drug_concept_id, and the dosing in quantity (for the amount) and drug_strength.amount_unit_concept_id. See approved proposals for [[http://www.ohdsi.org/web/wiki/doku.php?id=documentation:next_cdm:drug_strength_for_quantified|extension of DRUG_STRENGTH]] and for [[http://www.ohdsi.org/web/wiki/doku.php?id=documentation:next_cdm:denominator_units|dosing]].