In our design of a Data Dictionary for the Food Allergy Data Commons we are building we have found what seems to be a gap in the coverage of OMOP’s dictionary.
We are having difficulty coding for the procedure of Oral Immunotherapy.
Oral Immunotherapy takes place in cycles. In the first phase, OIT Initiation, a patient is given an initial small dose of a food compound in a clinical setting and monitored to find how much they are able to handle without having an allergic reaction. Then they return home and take that dose every day, referred to as Home Maintenance. At certain points they visit their doctor for an Up-dosing Visit where they find out if the patient can tolerate a larger amount, and then they return to the Home Maintenance phase.
The code we can find for this is the Measurement code – 43528012 – Ingestion Challenge Test. However this only covers the initial OIT Initiation stage and its classification as a Measurement does not seem correct for this procedure.
For the Home Maintenance phase, either the DEVICE_EXPOSURE or DRUG_EXPOSURE tables seem to fit what we want to represent, which is a patient constantly taking the food extract or compound everyday over a period of time. However we have no Drug or Device codes to represent this. Which of these two tables would work best? Are there existing codes to represent non FDA approved drugs without RxNorm codes, such as those made by a compounding pharmacy?
Finally we have no code for the up-dosing visit, the Ingestion Challenge Test covers only the initial visit. Is there any code we are missing that may cover this?