Hope that I don’t duplicate any topic.
We at STACC OÜ are currently mapping Estonian prescriptions data to OMOP CDM with the aim to map and combine three different data sources (prescriptions, claims and EHR records) in a pilot project.
Questions are related to prescription data. It’s an independent data-source, meaning there is no direct link to any inpatient or outpatient visit.
The prescriptions data-source contains:
prescribing information – the date prescription was written, information about prescribed drug, provider, patient’s condition (i.e. diagnosis), etc.
dispensing information – the date the drug was dispensed, information about dispensed drug, pharmacy, etc.
We would like to store in OMOP CDM both, prescribing information as well as dispensing information.
Note, that by our national regulations prescriptions can be valid up to 180 days (in some cases even more). Thus, the gap between prescription written and drug dispensed may be long, or sometimes the medication is not dispensed at all. We also have cases where we do not know if the drug will be dispensed or not (i.e. the prescription is valid, but the person has not purchased the drug yet).
The questions that we are currently struggling with:
- Is it OK that persons that have information about prescribing as well as dispensing can have basically two records in the DRUG_EXPOSURE table, i.e. one record about prescribing (with drug_type_concept_id ‘‘38000177 Prescription written’’) and one record about dispensing (with drug_type_concept_id ‘‘38000175 Prescription dispensed in pharmacy’’)?
If yes, then:
Is it possible to maintain the connection in OMOP CDM between prescribed drug and dispensed drug?
in case of a prescribing record, is it correct to set drug_exposure_start_date as a date on which the prescription was written? Even if we know based on dispensing information that drug utilization started later or the drug was never purchased?
If yes, then:
doesn’t that cause misleading information in the DRUG_ERA table? I mean if the time between prescription written and drug dispensed is longer than the standard Persistence Window of 30 days it could lead to multiple drug eras instead of one?
When the drug was not dispensed during the prescription validity period (person didn’t buy the drug), should the prescribing information added to the DRUG_EXPOSURE table although we know that the person didn’t took the drug prescribed with this prescription.
Any help would be appreciated.