st: Handling pharmacy data with multiple entries per subject

["Doernberg, Sarah" <Sarah.Doernberg@ucsf.edu>]

Hi all:

I have a dataset from our pharmacy with prescriptions for antibiotics in hospitalized patients. Each time a patient was transferred (from the emergency department to the ward or the ward to the ICU, for instance), a new prescription (and thus, a new row) was generated. This is compounded by the fact that some people received intermittent dosing (each start date with it's own row).

Because this is a very large set of data, I am trying to figure out how to have Stata combine the rows. Ideally, I would like to have one entry per person with consecutive courses of antibiotics represented by start and stop days (for example, someone who received an antibiotic from 6/1-6/3 and 6/7-6/9 would have start_date_1 = 6/1, stop_date_1=6/3 and start_date_2=6/7 and stop_date_2=6/9).

I have tried doing this with the collapse command but the best I can do is to get total days on antibiotic in a given month. Converting from long to wide also is not ideal because consecutive courses are not combined due to the multiple prescriptions based on location.

Does anyone have ideas or experience about how to handle this in Stata?

Thank you in advance for your help.

Best,

Sarah

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