Hello OHDSI community, I am very happy to join in! I am currently working on Mapping measurements from oral glucose tolerance tests (oGTT). There we take a blood sample at baseline, then administer a liquid containing glucose and take blood samples after 30, 60, 90 and 120 minutes in order to measure blood glucose at the different time intervals.
What has been done: I was able to find standard ids for fasting blood glucose measurements (4156660 - "Fasting blood glucose measurement), the 1 hour time interval (40482677 - “Measurement of glucose 1 hour after glucose challenge for glucose tolerance test”) and the 2 hour time interval (4176733 - “Measurement of glucose 2 hours after glucose challenge for glucose tolerance test”).
Problem: What I cannot seem to find are standard ids for the glucose measurements at the 30 and 90 minute time interval.
Question: How do I best map the glucose measurements at the time intervals after 30 and 90 minutes? Do I simply do that by setting the measurement_concept_id to 0 or can I do it in a more sophisticated way?
Proposed Ideas: I can think of setting the OGTT as an observation instead of a measurement and use qualifiers (there is one for 30 but not for 90 minutes: 4114365 - " 30 minutes post-dose"). Another alternative could be to work through the measurment_datetime or measurement_time field in the Measurement table. However, I only have the date and not the time of the measurement, I would need to set an arbitrary time point and increase the time interval from there.
Does anybody have experience with this kind of Mapping and/or has any tips or advice to provide? I am very grateful for any ideas!