If source data provides the drug and total quantity only (no daily dosage, no frequency, no days supplied, no end date), then we need to impute drug_exposure_end_date.
We can use 30 days as a default value, but it’s not precise enough.
Together with @zhuk and @Alexdavv we are trying to apply the ATC DDD approach (at least for oral solid forms) and found some pros and cons. Please find a couple of examples attached:
- ‘proportion, %’ column contains % of records for a combination of drug and total quantity in the source data
- ‘days_supply’ column is calculated value: drug strength * quantity / ddd
ATC DDD.xlsx (17.2 KB)
Our questions are the following:
- Has anybody tried to calculate the duration of taking the drug using ATC DDD?
- How did you deal with cases when DDD is not working (how did you automate that in your ETL?)?
- Did you build any heuristic based on quantity typical values (28/56/84/100/60/90)?
- Did you take into account the total quantity and ‘DDD / drug strength’ ratio? For example, if quantity > 30, then use DDD, if ‘DDD / drug strength’ > 2, then use DDD, otherwise use total quantity as duration days.