SDTM: SE Subject Element Domain

Background Story :

One day, my friend 99 discussed with me if a patient is randomized but not treated has some lab results besides screening, how should we classify the EPOCH variable for him/her in SE domain?
So today we will go over a basic example for SE domain: Subject Element.


The SE stores treatment data linked together with demographic data and Trial Design data,  which is possible to standardize and create unique data-driven mapping for a high level view of study.


SE (Subject Element) contains subject level data about the timings of each subject transition from one element period to the other (screening, treatment, follow-up) and the treatment information (active, non-active) from multiple sources.


Key Variables:


Variable Derivation Rules:

Sequential number is unique for the records within the domain by USUBJID.

Element Code is assigned (SCREEN, Treatment, Placebo, FUP).

Description of Element is assigned.(Screening, Treatment info, Follow up).

Start date of the element depends on Planned Arm
relates to Informed consent date, Reference start date, Treatment Exposure Date.

End date of the elements equal to the next SESTDTC of next element.

Planned Order of Elements within Arm is directly from TA

Epoch is directly from TE.EPOCH
it originated from to reference start/end date.


SE Mini Sample Data Set: 



Note: The dataset is a dummy sample, real data will have different SESTDTC, SEENDTC dates

To end the story we started, SE would only keep the Screening record for a patient without treatment even he/she has follow up records.

Thanks 99 for sharing a case study with me!

Happy Studying!


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