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Limit for days_supply, refills and quantity

(Olga Osintseva) #1

In Achilles Heel Report i find warning about limit of days_supply, refills and quantity.

WARNING: Distribution of days_supply by drug_concept_id; max value should not be > 180
WARNING: Distribution of refills by drug_concept_id; max value should not be > 10
WARNING: Distribution of quantity by drug_concept_id; max value should not be > 600

Does anybody know anything about these limitations? How are they determined?

Thank you in advance

(Chris Knoll) #2

The rules are defined here (bookmarked to the days supply rule definition):

The sourcecode to that rule is here:

In general, the way the heel reports work is that they look to the summary statistics (the maximum value of days supply, in this example) and will output a warning if the value is suspicious (in this case, a DRUG_EXPOSURE Record with a days supply of 180 is suspicious).

(Olga Osintseva) #3

Thank you!

(Alexandra Orlova) #4

Do you have any idea why Achilles limits days_supply / refills / quantity using exactly those numbers?
For example, Achilles states that quantity shouldn’t be more than 600. What does 600 mean? Tablets, milliliters or what? Each drug has its own units, not sure that it is correct to use such limitation. What do you think?
Same about refills and days supply. Do you know why those particular numbers are used? maybe, they are from some medical documentation?

(Julianna Kohler) #5

I think the relevant unit is days. So, patients don’t get more than about 2 years worth of drugs at a time (which seems pretty generous, in my experience).

(Alexandra Orlova) #6

the days_supply field captures info about a duration of taking a drug and this field has Achilles limit equaled 180 days, so according to Achilles patient cannot get more than half of a year worth of drugs at a time. And I’m wondering why 180 days limit is using? Same for refills.

the quantity field captures info about the quantity of drug (10 tablets, 100 mg, etc.) and this field has Achilles limit equaled 600. I cannot understand this limit at all. As I mentioned above each drug has its own units, but this limit is applied to all drugs. Is it correct?

(Christian Reich) #7

Because usually patients don’t get prescribed years worth of prescription drugs. They have to come back in to renew the prescription. There are exceptions, though (folks moving to some developing country or so), but that is rare.

True, but only half true. If the Drug Concept is an ingredient or Drug Component then the quantity is whatever unit the ingredient is assigned to. You can find that in DRUG_STRENGTH. We are revising the CDM and will explain that painstakingly. Right now it is all over the place.

(Christian Reich) #8


Days_supply - days
Refills - number without a unit
Quantity - sales unit if Clinical Drug or less, measurement unit if Ingredient or Drug Component.